The Kosovo War was an armed conflict in Kosovo that started in late February 1998^[50][51] and lasted until 11 June 1999.^[52] It was fought by the forces of the Federal Republic of Yugoslavia (i.e. Serbia and Montenegro), which controlled Kosovo before the war, and the Kosovo Albanian rebel group known as the Kosovo Liberation Army (KLA), with air support from the North Atlantic Treaty Organisation (NATO) from 24 March 1999, and ground support from the Albanian army.^[53]

The KLA, formed in the early 1990s to fight against Serbian persecution of Kosovo Albanians,^[54] initiated its first campaign in 1995 when it launched attacks against Serbian law enforcement in Kosovo. In June 1996 the group claimed responsibility for acts of sabotage targeting Kosovo police stations. In 1997, the organisation acquired a large amount of arms through weapons smuggling from Albania, following a rebellion in which weapons were looted from the country's police and army posts. In early 1998, KLA attacks targeting Yugoslav authorities in Kosovo resulted in an increased presence of Serb paramilitaries and regular forces who subsequently began pursuing a campaign of retribution targeting KLA sympathisers and political opponents;^[55] this campaign killed 1,500 to 2,000 civilians and KLA combatants.^[56][57]

After attempts at a diplomatic solution failed, NATO intervened, justifying the campaign in Kosovo as a "humanitarian war".^[58] This precipitated a mass expulsion of Kosovar Albanians as the Yugoslav forces continued to fight during the aerial bombardment of Yugoslavia (March–June 1999).^[59][60] By 2000, investigations had recovered the remains of almost three thousand victims of all ethnicities,^[61] and in 2001 a United Nations administered Supreme Court, based in Kosovo, found that there had been "a systematic campaign of terror, including murders, rapes, arsons and severe maltreatments", but that Yugoslav troops had tried to remove rather than eradicate the Albanian population.^[62]

The war ended with the Kumanovo Treaty, with Yugoslav and Serb forces^[63] agreeing to withdraw from Kosovo to make way for an international presence.^[64][65] The Kosovo Liberation Army disbanded soon after this, with some of its members going on to fight for the UÇPMB in the Preševo Valley^[66] and others joining the National Liberation Army (NLA) and Albanian National Army (ANA) during the armed ethnic conflict in Macedonia,^[67] while others went on to form the Kosovo Police.^[68] After the war, a list was compiled which documented that over 13,500 people were killed or went missing during the two year conflict.^[69] The Yugoslav and Serb forces caused the displacement of between 1.2 million^[70] to 1.45 million Kosovo Albanians.^[71] After the war, around 200,000 Serbs, Romani and other non-Albanians fled Kosovo and many of the remaining civilians were victims of abuse.^[72] Serbia became home to the highest number of refugees and IDPs in Europe.^[73][74]

The NATO bombing campaign has remained controversial, as it did not gain the approval of the UN Security Council and because it caused at least 488 Yugoslav civilian deaths,^[75] including substantial numbers of Kosovar refugees.^[76][77]

The modern Albanian-Serbian conflict has its roots in the expulsion of the Albanians in 1877-1878 from areas that became incorporated into the Principality of Serbia.^[78][79] Tensions between the Serbian and Albanian communities in Kosovo simmered throughout the 20th century and occasionally erupted into major violence, particularly during the First Balkan War (1912–13), World War I (1914–18), and World War II (1939–45). After 1945 the socialist government under Josip Broz Tito systematically repressed all manifestations of nationalism throughout Yugoslavia, seeking to ensure that no republic or nationality gained dominance over the others. In particular, Tito diluted the power of Serbia—the largest and most populous republic—by establishing autonomous governments in the Serbian province of Vojvodina in the north and Kosovo and Metohija in the south. Kosovo's borders did not precisely match the areas of ethnic Albanian settlement in Yugoslavia (significant numbers of Albanians remained in the Socialist Republic of Macedonia, Montenegro and Serbia). Kosovo's formal autonomy, established under the 1945 Yugoslav constitution, initially meant relatively little in practice. The secret police (the UDBA) cracked down hard on nationalists. In 1956 a number of Albanians went on trial in Kosovo on charges of espionage and subversion. The threat of separatism was in fact minimal, as the few underground groups aiming for union with Albania had little political significance. Their long-term impact became substantial, though, as some—particularly the Revolutionary Movement for Albanian Unity, founded by Adem Demaçi—would eventually form the political core of the Kosovo Liberation Army (founded in 1990). Demaci himself was imprisoned in 1964 along with many of his followers. Yugoslavia underwent a period of economic and political crisis in 1969, as a massive government program of economic reform widened the gap between the rich north and poor south of the country.

Student demonstrations and riots in Belgrade in June 1968 spread to Kosovo in November, but Yugoslav security forces quelled them. Tito conceded some of the students' demands—in particular, representative powers for Albanians in both the Serbian and Yugoslav state bodies and better recognition of the Albanian language. The University of Pristina was established as an independent institution in 1970, ending a long period when the institution had been run as an outpost of Belgrade University. The lack of Albanian-language educational materials in Yugoslavia hampered Albanian education in Kosovo, so an agreement was struck with Albania itself to supply textbooks.

In 1969 the Serbian Orthodox Church ordered its clergy to compile data on the ongoing problems of Serbs in Kosovo, seeking to pressure the government in Belgrade to do more to protect the interests of Serbs there.

In 1974 Kosovo's political status improved further when a new Yugoslav constitution granted an expanded set of political rights. Along with Vojvodina, Kosovo was declared a province and gained many of the powers of a fully-fledged republic: a seat on the federal presidency and its own assembly, police force and national bank.^[80]

Provincial power was still exercised by the Communist Party, but now devolved mainly to ethnic Albanian communists. Tito's death on 4 May 1980 ushered in a long period of political instability, worsened by growing economic crisis and nationalist unrest. The first major outbreak occurred in Kosovo's main city, Pristina, when a protest of University of Pristina students over long queues in their university canteen rapidly escalated and in late March and early April 1981 spread throughout Kosovo, causing mass demonstrations in several towns. The disturbances were quelled by the Presidency of Yugoslavia proclaiming a state of emergency, sending in riot police and the army, which resulted in numerous casualties.

Communist hard-liners instituted a fierce crackdown on nationalism of all kinds. Kosovo endured a heavy secret-police presence throughout most of the 1980s that ruthlessly suppressed any unauthorised nationalist manifestations, both Albanian and Serbian. According to a report quoted by Mark Thompson, as many as 580,000 inhabitants of Kosovo were arrested, interrogated, interned or reprimanded. Thousands of these lost their jobs or were expelled from their educational establishments. During this time tension between the Albanian and Serbian communities continued to escalate.

In February 1982 a group of priests from Serbia proper petitioned their bishops to ask "why the Serbian Church is silent" and why it did not campaign against "the destruction, arson and sacrilege of the holy shrines of Kosovo". Such concerns did attract interest in Belgrade. Stories appeared from time to time in the Belgrade media claiming that Serbs and Montenegrins were being persecuted. There was a perception among Serbian nationalists that Serbs were being driven out of Kosovo.

In addition to all this, the worsening state of Kosovo's economy made the province a poor choice for Serbs seeking work. Albanians, as well as Serbs, tended to favor their compatriots when hiring new employees, but the number of jobs was too few for the population. Kosovo was the poorest entity of Yugoslavia: the average per capita income was $795, compared with the national average of $2,635.

In 1981 it was reported that some 4,000 Serbs moved from Kosovo to central Serbia after the Kosovo Albanian riots in March that resulted in several Serb deaths and the desecration of Serbian Orthodox architecture and graveyards.^[81] Serbia reacted with a plan to reduce the power of Albanians in the province and a propaganda campaign that claimed Serbs were being pushed out of the province primarily by the growing Albanian population, rather than the bad state of the economy.^[82] 33 nationalist formations were dismantled by Yugoslav police, who sentenced some 280 people (800 fined, 100 under investigation) and seized arms caches and propaganda material.^[83]

In 1987 David Binder wrote in The New York Times about the growing ethnic tension in Yugoslavia and rising nationalism among Albanians in Kosovo and referred to the Paraćin massacre, where an ethnic Albanian soldier in the JNA killed four fellow soldiers.^[84] Binder also—writing of Slobodan Milošević's deposing of Dragiša Pavlović as head of Belgrade's party organisation shortly before—wrote that "Mr. Milosevic accused Mr. Pavlovic of being an appeaser who was soft on Albanian radicals", and that "Mr. Milosevic and his supporters appear to be staking their careers on a strategy of confrontation with the Kosovo ethnic Albanians".^[84] The article quotes the Federal Secretary for National Defence, Fleet Adm. Branko Mamula, who claimed that "from 1981 to 1987, 216 illegal Albanian organisations with 1,435 members were discovered in the JNA". Mamula had also said that ethnic Albanian subversives had been preparing for "killing officers and soldiers, poisoning food and water, sabotage, breaking into weapons arsenals and stealing arms and ammunition, desertion and causing flagrant nationalist incidents in army units".^[84]

In Kosovo an increasingly poisonous atmosphere between Serbs and Albanians led to wild rumors being spread and otherwise trivial incidents being blown out of proportion. It was against this tense background that the Serbian Academy of Sciences and Arts (SANU) conducted a survey of Serbs who had left Kosovo in 1985 and 1986, which concluded that a considerable number had left under pressure from Albanians.^[85]

The so-called SANU Memorandum, leaked in September 1986, was a draft document that focused on the political difficulties facing Serbs in Yugoslavia, pointing to Tito's deliberate hobbling of Serbia's power and the difficulties faced by Serbs outside Serbia proper. It paid special attention to Kosovo, arguing that the Kosovo Serbs were being subjected to "physical, political, legal and cultural genocide" in an "open and total war" that had been ongoing since the spring of 1981. It claimed that Kosovo's status in 1986 was a worse historical defeat for the Serbs than any event since liberation from the Ottomans in 1804, thus ranking it above such catastrophes as the World war occupations. The Memorandum's authors claimed that 200,000 Serbs had moved out of the province over the previous 20 years and warned that there would soon be none left "unless things change radically." The remedy, according to the Memorandum, was for "genuine security and unambiguous equality for all peoples living in Kosovo and Metohija [to be] established" and "objective and permanent conditions for the return of the expelled [Serbian] nation [to be] created." It concluded that "Serbia must not be passive and wait and see what the others will say, as it has done so often in the past." The SANU Memorandum provoked split reactions: Albanians saw it as a call for Serbian supremacy at the local level, claiming the Serb emigrants had left Kosovo for economic reasons, while the Slovenes and Croats saw a threat in the call for a more assertive Serbia. Serbs were divided: many welcomed it, while the Communist old guard strongly attacked its message. One of those who denounced it was Serbian Communist Party official Slobodan Milošević.

In November 1988 Kosovo's head of the provincial committee was arrested. In March 1989 Milošević announced an "anti-bureaucratic revolution" in Kosovo and Vojvodina, curtailing their autonomy as well as imposing a curfew and a state of emergency in Kosovo due to violent demonstrations, resulting in 24 deaths (including two policemen). Milošević and his government claimed that the constitutional changes were necessary to protect Kosovo's remaining Serbs against harassment from the Albanian majority.

On 17 November 1988 Kaqusha Jashari and Azem Vllasi were forced to resign from the leadership of the League of Communists of Kosovo (LCK).^[86][87][88] In early 1989 the Serbian Assembly proposed amendments to the Constitution of Serbia that would remove the word "Socialist" from the Serbian Republic's title, establish multi-party elections, remove the independence of institutions of the autonomous provinces such as Kosovo and rename Kosovo as the Autonomous Province of Kosovo and Metohija.^[89][90] In February Kosovar Albanians demonstrated in large numbers against the proposal, emboldened by striking miners.^[88][91] Serbs in Belgrade protested against the Kosovo Albanian's separatism.^[92] On 3 March 1989 the Presidency of Yugoslavia imposed special measures assigning responsibility for public security to the federal government.^[91] On 23 March the Assembly of Kosovo voted to accept the proposed amendments although most Albanian delegates abstained.^[91] In early 1990 Kosovar Albanians held mass demonstrations against the special measures, which were lifted on 18 April 1990 and responsibility for public security was again assigned to Serbia.^[91][93]

On 8 May 1989 Milošević became President of the Presidency of Serbia, which was confirmed on 6 December.^[91] On 22 January 1990 the 14th congress of the League of Communists of Yugoslavia (LCY) abolished the party's position as the only legal political party in Yugoslavia.^[94] In January 1990 the Yugoslav government announced it would press ahead with the creation of a multi-party system.^[94]

On 26 June 1990 Serbian authorities closed the Kosovo Assembly, citing special circumstances.^[93] On 1 or 2 July 1990 Serbia approved the new amendments to the Constitution of Serbia in a referendum.^[93][95] Also on 2 July, 114 ethnic Albanian delegates of the 180-member Kosovo Assembly declared Kosovo an independent republic within Yugoslavia.^[93][91] On 5 July the Serbian Assembly dissolved the Kosovo Assembly.^[93][91] Serbia also dissolved the provincial executive council and assumed full and direct control of the province.^[96] Serbia took over management of Kosovo's principal Albanian-language media, halting Albanian-language broadcasts.^[96] On 4 September 1990 Kosovar Albanians observed a 24-hour general strike, virtually shutting down the province.^[96]

On 16 or 17 July 1990 the League of Communists of Serbia (LCS) combined with the Socialist Alliance of Working People of Serbia to become the Socialist Party of Serbia (SPS), and Milošević became its first president.^[97][91] On 8 August 1990 several amendments to the federal Socialist Federal Republic of Yugoslavia (SFRY) Constitution were adopted enabling the establishment of a multi-party election system.^[95]

On 7 September 1990 the Constitution of the Republic of Kosovo was promulgated by the disbanded Assembly of Kosovo.^[95] Milošević responded by ordering the arrest of the deputies of the disbanded Assembly of Kosovo.^[96] The new controversial Serbian Constitution was promulgated on 28 September 1990.^[90] Multi-party elections were held in Serbia on 9 and 26 December 1990 after which Milošević became President of Serbia.^[91] In September 1991 Kosovar Albanians held an unofficial referendum in which they voted overwhelmingly for independence.^[91] On 24 May 1992 Kosovar Albanians held unofficial elections for an assembly and president of the Republic of Kosovo.^[91]

On 5 August 1991 the Serbian Assembly suspended the Priština daily Rilindja,^[96][98] following the Law on Public Information of 29 March 1991 and establishment of the Panorama publishing house on 6 November which incorporated Rilindja, which was declared unconstitutional by the federal authorities.^[99] United Nations Special Rapporteur Tadeusz Mazowiecki reported on 26 February 1993 that the police had intensified their repression of the Albanian population since 1990, including depriving them of their basic rights, destroying their educations system, and large numbers of political dismissals of civil servants.^[99]

Ibrahim Rugova, first President of the Republic of Kosova, pursued a policy of passive resistance which succeeded in maintaining peace in Kosovo during the earlier wars in Slovenia, Croatia and Bosnia during the early 1990s. As evidenced by the emergence of the Kosovo Liberation Army (KLA), this came at the cost of increasing frustration among Kosovo's Albanian population. In the mid-1990s, Rugova pleaded for a United Nations peacekeeping force for Kosovo. In 1997, Milošević was promoted to the presidency of the Federal Republic of Yugoslavia (comprising Serbia and Montenegro since its inception in April 1992).

Continuing repression convinced many Albanians that only armed resistance would change the situation. On 22 April 1996, four attacks on Serbian security personnel were carried out almost simultaneously in several parts of Kosovo. The KLA, a hitherto-unknown organisation, subsequently claimed responsibility. The nature of the KLA was at first mysterious. It initially seemed that their only goals were to stop repression from Yugoslav authorities.

As stated by Jakup Krasniqi, who was the spokesman of the group, the KLA was formed by some members from the Democratic League of Kosovo (LDK), a political party led by Rugova.^[100] The KLA and LDK shared the common goal of ending repression from Belgrade and making Kosovo independent, but the KLA was opposed to 'internal rule' of Kosovo by the LDK.^[100]

KLA goals also included the establishment of a Greater Albania, a state stretching into surrounding FYR Macedonia, Montenegro and southern Serbia.^[100][101] In July 1998, in an interview for Der Spiegel, Jakup Krasniqi publicly announced that the KLA's goal was the unification of all Albanian-inhabited lands.^[101] Sulejman Selimi, a General Commander of KLA in 1998-1999, said: ^[100]

While Rugova promised to uphold the minority rights of Serbs in Kosovo, the KLA was much less tolerant. Selimi stated that "Serbs who have blood on their hands would have to leave the Kosovo".^[100]

It is widely believed that the KLA received financial and material support from the Kosovo Albanian diaspora.^[102][103] In early 1997, Albania collapsed into chaos following the fall of President Sali Berisha. Military stockpiles were looted with impunity by criminal gangs, with much of the hardware ending up in western Kosovo and boosting the growing KLA arsenal. Bujar Bukoshi, shadow Prime Minister in exile (in Zürich, Switzerland), created a group called FARK (Armed Forces of the Republic of Kosova), which was reported to have been disbanded and absorbed by the KLA in 1998. The Yugoslav government considered the KLA to be "terrorists" and "insurgents" who indiscriminately attacked police and civilians, while most Albanians saw the KLA as "freedom fighters".

In 1998, the US State Department listed the KLA as a terrorist organisation,^[103] and in 1999 the Republican Policy Committee of the US Senate expressed its troubles with the "effective alliance" of the Democratic Clinton administration with the KLA due to "numerous reports from reputable unofficial sources".^[104] In 2004, John Pilger claimed that for six years prior to 1998, the KLA had been regarded by the US as a terrorist group.^[105] Early in 1998, US envoy Robert Gelbard referred to the KLA as terrorists;^[106] responding to criticism, he later clarified to the House Committee on International Relations that "while it has committed 'terrorist acts,' it has 'not been classified legally by the U.S. Government as a terrorist organization.'"^[104] In June 1998, he held talks with two men who claimed they were political leaders of the KLA.^[106] In 2000, a BBC documentary called Moral Combat – Nato at War showed how the United States now sought a relationship with the group.^[107] While the US officially described the KLA as terrorists, author Alastair MacKenzie claims the KLA received training by the Americans' closest NATO-ally, the United Kingdom, since 1998 in a training camp in the mountains above the northern Albanian town of Bajram Curri.^[108]

Meanwhile, the US held an "outer wall of sanctions" on Yugoslavia which had been tied to a series of issues, including Kosovo. These were maintained despite the agreement at Dayton to end all sanctions. The Clinton administration claimed that the agreement bound Yugoslavia to hold discussions with Rugova over Kosovo.

The crisis escalated in December 1997 at the Peace Implementation Council meeting in Bonn, where the international community (as defined in the Dayton Agreement) agreed to give the High Representative in Bosnia and Herzegovina sweeping powers, including the right to dismiss elected leaders. At the same time, Western diplomats insisted that Kosovo be discussed, and that Yugoslavia be responsive to Albanian demands there. The delegation from Yugoslavia stormed out of the meetings in protest.^[109] This was followed by the return of the Contact Group that oversaw the last phases of the Bosnian conflict and declarations from European powers demanding that Yugoslavia solve the problem in Kosovo.

KLA attacks intensified, centering on the Drenica valley area with the compound of Adem Jashari being a focal point. Days after Robert Gelbard described the KLA as a terrorist group, Serbian police responded to the KLA attacks in the Likošane area, and pursued some of the KLA to Čirez, resulting in the deaths of 16 Albanian fighters^[110] and four Serbian policemen.^[111] The KLA's goal was to merge its Drenica stronghold with their stronghold in Albania proper, and this would shape the first few months of the fighting.

Despite some accusations of summary executions and killings of civilians, condemnations from Western capitals were not as voluble as they would become later. Serb police began to pursue Jashari and his followers in the village of Donje Prekaze. On March 5, 1998, a massive firefight at the Jashari compound led to the massacre of 60 Albanians, of which eighteen were women and ten were under the age of sixteen.^[112] The event provoked massive condemnation from western capitals. Madeleine Albright said that "this crisis is not an internal affair of the FRY".^[113]

On March 24, Yugoslav forces surrounded the village of Glodjane and attacked a rebel compound there.^[114] Despite superior firepower, the Yugoslav forces failed to destroy the KLA unit, which had been their objective. Although there were deaths and severe injuries on the Albanian side, the insurgency in Glodjane was far from stamped out. It was in fact to become one of the strongest centres of resistance in the upcoming war.

A new Yugoslav government was formed at this time, led by the Socialist Party of Serbia and the Serbian Radical Party. Ultra-nationalist Radical Party chairman Vojislav Šešelj became a deputy prime minister. This increased the dissatisfaction with the country's position among Western diplomats and spokespersons.

In early April, Serbia arranged for a referendum on the issue of foreign interference in Kosovo. Serbian voters decisively rejected foreign interference in the crisis.^[115] Meanwhile, the KLA claimed much of the area in and around Deçan and ran a territory based in the village of Glodjane, encompassing its surroundings. On May 31, 1998, the Yugoslav army and the Serb Ministry of the Interior police began an operation to clear the border of the KLA. NATO's response to this offensive was mid-June's Operation Determined Falcon, a NATO show of force over the Yugoslav borders.^[116]

During this time, Yugoslav President Milošević reached an arrangement with Boris Yeltsin of Russia to stop offensive operations and prepare for talks with the Albanians, who refused to talk to the Serbian side throughout the crisis, but would talk with the Yugoslav government. In fact, the only meeting between Milošević and Ibrahim Rugova happened on 15 May in Belgrade, two days after Richard Holbrooke announced that it would take place. Holbrooke threatened Milošević that if he did not obey, "what's left of your country will implode". A month later, Holbrooke visited the border areas affected by the fighting in early June, where he was famously photographed with the KLA. The publication of these images sent a signal to the KLA, its supporters and sympathisers, and to observers in general, that the US was decisively backing the KLA and the Albanian population in Kosovo.

The Yeltsin agreement required Milošević to allow international representatives to set up a mission in Kosovo to monitor the situation there. The Kosovo Diplomatic Observer Mission (KDOM) began operations in early July 1998. The US government welcomed this part of the agreement, but denounced the initiative's call for a mutual cease fire. Rather, the US demanded that the Serbian-Yugoslavian side should cease fire "without linkage ... to a cessation in terrorist activities".

All through June and into mid-July, the KLA maintained its advance. The KLA surrounded Peć and Đakovica, and set up an interim capital in the town of Mališevo (north of Orahovac). KLA troops infiltrated Suva Reka and the northwest of Pristina. They moved on to capture the Belacevec coal pits in late June, threatening energy supplies in the region. Their tactics as usual focused mainly on guerilla and mountain warfare, and harassing and ambushing Yugoslav forces and Serb police patrols.

The tide turned in mid-July when the KLA captured Orahovac. On 17 July 1998, two nearby villages, Retimlije and Opteruša, were also captured, while less systematic events took place in the larger Serb-populated village of Velika Hoča. The Orthodox monastery of Zociste three miles (4.8 km) from Orehovac—famous for the relics of the Saints Kosmas and Damianos and revered also by local Albanians—was robbed, its monks deported to a KLA prison camp, and, while empty, the monastery church and all its buildings were levelled to the ground by mining. This led to a series of Serb and Yugoslav offensives which would continue into the beginning of August.

A new set of KLA attacks in mid-August triggered Yugoslavian operations in south-central Kosovo, south of the Pristina-Peć road. This wound down with the capture of Klečka on August 23 and the discovery of a KLA-run crematorium in which some of their victims were found. The KLA began an offensive on September 1 around Prizren, causing Yugoslavian military activity there. In western Kosovo, around Peć, another offensive caused condemnation as international officials expressed fear that a large column of displaced people would be attacked.

In early mid-September, for the first time, KLA activity was reported in northern Kosovo around Podujevo. Finally, in late September, a determined effort was made to clear the KLA out of the northern and central parts of Kosovo and out of the Drenica valley itself. During this time many threats were made from Western capitals but these were tempered somewhat by the elections in Bosnia, as they did not want Serbian Democrats and Radicals to win. Following the elections, the threats intensified once again, but a galvanising event was needed. They got it on September 28, when the mutilated corpses of a family were discovered by KDOM outside the village of Gornje Obrinje. The bloody image of a child's doll and streams of displaced persons rallied the international community to action.^[117]

Morale was a serious problem for Serb forces; intelligence surveys found that many soldiers disagreed with their comrades' actions. One tank commander reported, "for the entire time I was in Kosovo, I never saw an enemy soldier and my unit was never once involved in firing at enemy targets. The tanks which cost $2.5 million each were used to slaughter Albanian children... I am ashamed".^[118]

When retreating from Kosovo after NATO intervention, Yugoslav units appeared combat effective with high morale and displaying large holdings of undamaged equipment.^[119] Weeks before the end of hostilities, David Fromkin noted that "it seemed possible that NATO unity might crack before Yugoslav morale did."^[120] The announcement by President Clinton that the US would not deploy ground troops gave a tremendous boost to Serbian morale.^[121]

On 9 June 1998, US President Bill Clinton declared a "national emergency" (state of emergency) due to the "unusual and extraordinary threat to the national security and foreign policy of the United States" imposed by Yugoslavia and Serbia over the Kosovo War.^[122]

On 23 September 1998, acting under Chapter VII of the United Nations Charter, the UN Security Council adopted Resolution 1199. This expressed 'grave concern' at reports reaching the Secretary General that over 230,000 people had been displaced from their homes by 'the excessive and indiscriminate use of force by Serbian security forces and the Yugoslav Army',^[123] demanding that all parties in Kosovo and the Federal Republic of Yugoslavia cease hostilities and maintain a ceasefire. On 24 September the North Atlantic Council (NAC) of NATO issued an "activation warning" taking NATO to an increased level of military preparedness for both a limited air option and a phased air campaign in Kosovo.^[124] The other major issue for those who saw no option but to resort to the use of force was the estimated 250,000 displaced Albanians, 30,000 of whom were out in the woods, without warm clothing or shelter, with winter fast approaching.

Meanwhile, the US Ambassador to the Republic of Macedonia, Christopher Hill, was leading shuttle diplomacy between an Albanian delegation, led by Rugova, and the Yugoslav and Serbian authorities. These meetings were shaping the peace plan to be discussed during a period of planned NATO occupation of Kosovo. During a period of two weeks, threats intensified, culminating in NATO's Activation Order being given. NATO was ready to begin airstrikes, and Richard Holbrooke went to Belgrade in the hope of reaching an agreement with Milošević. Officially, the international community demanded an end to fighting. It specifically demanded that Yugoslavia end its offensives against the KLA whilst attempting to convince the KLA to drop its bid for independence. Attempts were made to persuade Milošević to permit NATO peacekeeping troops to enter Kosovo. This, they argued, would allow for the Christopher Hill peace process to proceed and yield a peace agreement.

On 13 October 1998, the North Atlantic Council issued activation orders for the execution of both limited air strikes and a phased air campaign in Yugoslavia which would begin in approximately 96 hours.^[125] On 15 October the NATO Kosovo Verification Mission (KVM) Agreement for a ceasefire was signed, and the deadline for withdrawal was extended to 27 October.^[126][127] Difficulties implementing the agreement were reported, as clashes continued between government troops and the guerrillas.^[128] The Serbian withdrawal commenced on or around 25 October 1998, and Operation Eagle Eye commenced on 30 October.^[126][127]

The KVM was a large contingent of unarmed Organization for Security and Co-operation in Europe (OSCE) peace monitors (officially known as verifiers) that moved into Kosovo. Their inadequacy was evident from the start. They were nicknamed the "clockwork oranges" in reference to their brightly coloured vehicles. Fighting resumed in December 1998 after both sides broke the ceasefire,^[129] and this surge in violence culminated in the killing of Zvonko Bojanić, the Serb mayor of the town of Kosovo Polje. Yugoslav authorities responded by launching a crackdown against KLA militants.^[130]

The January to March 1999 phase of the war brought increasing insecurity in urban areas, including bombings and murders. Such attacks took place during the Rambouillet talks in February and as the Kosovo Verification Agreement unraveled in March. Killings on the roads continued and increased. There were military confrontations in, among other places, the Vučitrn area in February and the heretofore unaffected Kačanik area in early March.

On 15 January 1999 the Račak massacre occurred when "45 Kosovan Albanian farmers were rounded up, led up a hill and massacred".^[131] The bodies had been discovered by OSCE monitors, including Head of Mission William Walker, and foreign news correspondents.^[132][133] Yugoslavia denied a massacre took place.^[133] The Račak massacre was the culmination of the KLA attacks and Yugoslav reprisals that had continued throughout the winter of 1998–1999. The incident was immediately condemned as a massacre by the Western countries and the United Nations Security Council, and later became the basis of one of the charges of war crimes leveled against Milošević and his top officials. This massacre was the turning point of the war. NATO decided that the conflict could only be settled by introducing a military peacekeeping force under the auspices of NATO, to forcibly restrain the two sides. Pristina, the capital of Kosovo, had been subjected to heavy firefights and segregation according to OSCE reports.^[134]

On 30 January 1999 NATO issued a statement announcing that the North Atlantic Council had agreed that "the NATO Secretary General may authorise air strikes against targets on FRY territory" to "[compel] compliance with the demands of the international community and [to achieve] a political settlement".^[135] While this was most obviously a threat to the Milošević government, it also included a coded threat to the Albanians: any decision would depend on the "position and actions of the Kosovo Albanian leadership and all Kosovo Albanian armed elements in and around Kosovo."^[135]

Also on 30 January 1999 the Contact Group issued a set of "non-negotiable principles" which made up a package known as "Status Quo Plus"—effectively the restoration of Kosovo's pre-1990 autonomy within Serbia, plus the introduction of democracy and supervision by international organisations. It also called for a peace conference to be held in February 1999 at the Château de Rambouillet, outside Paris.

The Rambouillet talks began on 6 February 1999, with NATO Secretary General Javier Solana negotiating with both sides. They were intended to conclude by 19 February. The FR Yugoslavian delegation was led by then president of Serbia Milan Milutinović, while Milošević himself remained in Belgrade. This was in contrast to the 1995 Dayton conference that ended the war in Bosnia, where Milošević negotiated in person. The absence of Milošević was interpreted as a sign that the real decisions were being made back in Belgrade, a move that aroused criticism in Yugoslavia as well as abroad; Kosovo's Serbian Orthodox bishop Artemije traveled all the way to Rambouillet to protest that the delegation was wholly unrepresentative. At this time speculation about an indictment of Milošević for war crimes was rife, so his absence may have been motivated by fear of arrest.

The first phase of negotiations was successful. In particular, a statement was issued by the Contact Group co-chairmen on 23 February 1999 that the negotiations "have led to a consensus on substantial autonomy for Kosovo, including on mechanisms for free and fair elections to democratic institutions, for the governance of Kosovo, for the protection of human rights and the rights of members of national communities; and for the establishment of a fair judicial system". They went on to say that "a political framework is now in place", leaving the further work of finalising "the implementation Chapters of the Agreement, including the modalities of the invited international civilian and military presence in Kosovo".

While the accords did not fully satisfy the Albanians, they were much too radical for the Yugoslavs, who responded by substituting a drastically revised text that even Russia (ally of FR Yugoslavia) found unacceptable. It sought to reopen the painstakingly negotiated political status of Kosovo and deleted all of the proposed implementation measures. Among many other changes in the proposed new version, it eliminated the entire chapter on humanitarian assistance and reconstruction, removed virtually all international oversight and dropped any mention of invoking "the will of the people [of Kosovo]" in determining the final status of the province.

On 18 March 1999, the Albanian, US, and British delegations signed what became known as the Rambouillet Accords, while the Yugoslav and Russian delegations refused. The accords called for NATO administration of Kosovo as an autonomous province within Yugoslavia, a force of 30,000 NATO troops to maintain order in Kosovo; an unhindered right of passage for NATO troops on Yugoslav territory, including Kosovo; and immunity for NATO and its agents to Yugoslav law. They would have also permitted a continuing Yugoslav army presence of 1,500 troops for border monitoring, backed by up to 1,000 troops to perform command and support functions, as well as a small number of border police, 2,500 ordinary MUP for public security purposes (although these were expected to draw down and to be transformed), and 3,000 local police.^[136]

Although the Yugoslav Government cited military provisions of Appendix B of the Rambouillet provisions as the reason for its objections, claiming that it was an unacceptable violation of Yugoslavia's sovereignty, these provisions were essentially the same as had been applied to Bosnia for the SFOR (Stabilisation Force) mission there after the Dayton Agreement in 1995. The two sides did not discuss the issue in detail because of their disagreements on more fundamental problems.^[137] In particular, the Serb side rejected the idea of any NATO troop presence in Kosovo to replace their security forces, preferring unarmed UN observers. Milošević himself had refused to discuss the annex after informing NATO that it was unacceptable, even after he was asked to propose amendments to the provisions which would have made them acceptable.^[138]

After the failure at Rambouillet and the alternative Yugoslav proposal, international monitors from the OSCE withdrew on 22 March, to ensure their safety ahead of the anticipated NATO bombing campaign.^[139] On 23 March, the Serbian assembly accepted the principle of autonomy for Kosovo, as well as the non-military aspects of the agreement, but rejected a NATO troop presence.^[139][140]

On 23 March 1999 at 21:30 UTC, Richard Holbrooke returned to Brussels and announced that peace talks had failed and formally handed the matter to NATO for military action.^[141][142] Hours before the announcement, Yugoslavia announced on national television it had declared a state of emergency, citing an imminent threat of war and began a huge mobilisation of troops and resources.^[141][143]

On 23 March 1999 at 22:17 UTC, the Secretary General of NATO, Javier Solana, announced he had directed the Supreme Allied Commander Europe (SACEUR), US Army General Wesley Clark, to "initiate air operations in the Federal Republic of Yugoslavia."^[143][144] On 24 March at 19:00 UTC, NATO started its bombing campaign against Yugoslavia.^[145][146]

The NATO bombing campaign lasted from 24 March to 11 June 1999, involving up to 1,000 aircraft operating mainly from bases in Italy and aircraft carriers stationed in the Adriatic. Tomahawk cruise missiles were also extensively used, fired from aircraft, ships, and submarines. With the exception of Greece, all NATO members were involved to some degree. Over the ten weeks of the conflict, NATO aircraft flew over 38,000 combat missions. For the German Air Force (Luftwaffe), it was the second time it had participated in a conflict since World War II, after the Bosnian War.

The proclaimed goal of the NATO operation was summed up by its spokesman as "Serbs out, peacekeepers in, refugees back". That is, Yugoslav troops would have to leave Kosovo and be replaced by international peacekeepers to ensure that the Albanian refugees could return to their homes. The campaign was initially designed to destroy Yugoslav air defences and high-value military targets. It did not go very well at first, with bad weather hindering many sorties early on. NATO had seriously underestimated Milošević's will to resist: few in Brussels thought that the campaign would last more than a few days, and although the initial bombardment was not insignificant, it did not match the intensity of the bombing of Baghdad in 1991.

NATO military operations switched increasingly to attacking Yugoslav units on the ground, hitting targets as small as individual tanks and artillery pieces, as well as continuing with the strategic bombardment. This activity was heavily constrained by politics, as each target needed to be approved by all nineteen member states. Montenegro was bombed on several occasions, but NATO eventually desisted to prop up the precarious position of its anti-Milošević leader, Milo Đukanović.

At the start of May, a NATO aircraft attacked an Albanian refugee convoy, believing it was a Yugoslav military convoy, killing around fifty people. NATO admitted its mistake five days later, and the Yugoslavs accused NATO of deliberately attacking the refugees. A later report conducted by the International Criminal Tribunal for the former Yugoslavia (ICTY) opined that "civilians were not deliberately attacked in this incident", and that "neither the aircrew nor their commanders displayed the degree of recklessness in failing to take precautionary measures which would sustain criminal charges."^[147] On May 7, NATO bombs hit the Chinese Embassy in Belgrade, killing three Chinese journalists and outraging Chinese public opinion. The United States and NATO later apologised for the bombing, saying that it occurred because of an outdated map provided by the CIA, although this was challenged by a joint report from The Observer (UK) and Politiken (Denmark) newspapers,^[148] which claimed that NATO intentionally bombed the embassy because it was being used as a relay station for Yugoslav army radio signals. The report by the newspaper contradicts findings in the same report by the ICTY which stated that the root of the failures in target location "appears to stem from the land navigation techniques employed by an intelligence officer."^[149] In another incident at the Dubrava prison in Kosovo in May 1999, the Yugoslav government attributed as many as 95 civilian deaths to NATO bombing of the facility after NATO cited Serbian and Yugoslav military activity in the area;^[150] a Human Rights Watch report later concluded that at least nineteen ethnic Albanian prisoners had been killed by the bombing, but that an uncertain number – probably more than 70 – were killed by Serbian Government forces in the days immediately following the bombing.^[150]

By the start of April, the conflict appeared little closer to a resolution, and NATO countries began to seriously consider conducting ground operations in Kosovo. British Prime Minister Tony Blair was a strong advocate of ground forces and pressured the United States to agree; his strong stance caused some alarm in Washington as US forces would be making the largest contribution to any offensive.^[151] US President Bill Clinton was extremely reluctant to commit US forces for a ground offensive. Instead, Clinton authorised a CIA operation to look into methods to destabilise the Yugoslav government without training KLA troops.^[152] At the same time, Finnish and Russian diplomatic negotiators continued to try to persuade Milošević to back down. Tony Blair would order 50,000 British soldiers to be made ready for a ground offensive: most of the available British Army.^[151]

Milošević finally recognised that Russia would not intervene to defend Yugoslavia despite Moscow's strong anti-NATO rhetoric. He thus accepted the conditions offered by a Finnish–Russian mediation team and agreed to a military presence within Kosovo headed by the UN, but incorporating NATO troops.

The Norwegian special forces Hærens Jegerkommando and Forsvarets Spesialkommando cooperated with the KLA in gathering intelligence information. Preparing for an invasion on 12 June, Norwegian special forces worked with the KLA on the Ramno mountain on the border between Macedonia and Kosovo and acted as scouts to monitor events in Kosovo. Together with British special forces, Norwegian special forces were the first to cross over the border into Kosovo. According to Keith Graves with the television network Sky News, the Norwegians were in Kosovo two days prior to the entry of other forces and were among the first into Pristina.^[153] The Hærens Jegerkommando's and Forsvarets Spesialkommando's job was to clear the way between the contending parties and to make local deals to implement the peace deal between the Serbians and the Kosovo Albanians.^[154][155]

On 3 June 1999, Milošević accepted the terms of an international peace plan to end the fighting, with the national parliament adopting the proposal amid contentious debate with delegates coming close to fistfights at some points.^[156][157] On 10 June, the North Atlantic Council ratified the agreement and suspended air operations.^[158]

On 12 June, after Milošević accepted the conditions, the NATO-led peacekeeping Kosovo Force (KFOR) of 30,000 soldiers began entering Kosovo. KFOR had been preparing to conduct combat operations, but in the end, its mission was only peacekeeping. The force was based upon the Allied Rapid Reaction Corps headquarters commanded by then Lieutenant General Mike Jackson of the British Army. It consisted of British forces (a brigade built from 4th Armored and 5th Airborne Brigades), a French Army Brigade, a German Army brigade, which entered from the west, while other forces advanced from the south, and Italian Army and United States Army brigades.

The first NATO troops to enter Pristina on the 12th of June 1999 were Norwegian special forces from Forsvarets Spesialkommando (FSK) and soldiers from the British Special Air Service 22 Regiment, although to NATO's diplomatic embarrassment Russian troops arrived at the airport first. Norwegian soldiers were the first to come into contact with Russian troops at the airport. FSK's mission was to level the negotiating field between the belligerent parties, and to fine-tune the detailed, local deals needed to implement the peace deal between the Serbians and the Kosovo Albanians.^{[159][160][161][162]}

The US contribution, known as the Initial Entry Force, was led by the 1st Armored Division, commanded by Brigadier General Peterson, and was spearheaded by a platoon from the 2nd Battalion, 505th Parachute Infantry Regiment attached to the British Forces. Other units included 1st and 2nd Battalions of the 10th Special Forces Group(Airborne) from Stuttgart Germany and Fort Carson, Colorado, TF 1–6 Infantry (1-6 infantry with C Co 1-35AR) from Baumholder, Germany, the 2nd Battalion, 505th Parachute Infantry Regiment from Fort Bragg, North Carolina, the 26th Marine Expeditionary Unit from Camp Lejeune, North Carolina, the 1st Battalion, 26th Infantry Regiment from Schweinfurt, Germany, and Echo Troop, 4th Cavalry Regiment, also from Schweinfurt, Germany. Also attached to the US force was the Greek Army's 501st Mechanised Infantry Battalion. The initial US forces established their area of operation around the towns of Uroševac, the future Camp Bondsteel, and Gnjilane, at Camp Monteith, and spent four months—the start of a stay which continues to date—establishing order in the southeast sector of Kosovo.

During the initial incursion, the US soldiers were greeted by Albanians cheering and throwing flowers as US soldiers and KFOR rolled through their villages. Although no resistance was met, three US soldiers from the Initial Entry Force were killed in accidents.^[163]

On 1 October 1999, approximately 150 paratroopers from Alpha Company, 1/508th Airborne Battalion Combat Team from Vicenza, Italy parachuted into Uroševac as part of Operation Rapid Guardian. The purpose of the mission was primarily to warn Yugoslav President Slobodan Milošević of NATO resolve and of its rapid military capability. One US soldier, Army Ranger Sgt. Jason Neil Pringle, was killed during operations after his parachute failed to deploy. The paratroopers of the 1/508th then joined paratroopers of the 82nd Airborne and KFOR in patrolling various areas of Kosovo, without incident, through 3 October 1999.

On 15 December 1999, Staff Sergeant Joseph Suponcic of 3rd Battalion/10th Special Forces Group (Airborne) was killed, when the HMMWV in which he was a passenger struck an anti-tank mine planted by Albanians and meant for the Russian contingent with which SSG Suponcic's team was patrolling in Kosovska Kamenica.

Following the military campaign, the involvement of Russian peacekeepers proved to be tense and challenging to the NATO Kosovo force. The Russians expected to have an independent sector of Kosovo, only to be unhappily surprised with the prospect of operating under NATO command. Without prior communication or coordination with NATO, Russian peacekeeping forces entered Kosovo from Bosnia and Herzegovina and occupied Pristina International Airport ahead of the arrival of NATO forces. This resulted in an incident during which NATO Supreme Commander Wesley Clark's wish to forcibly block the runways with NATO vehicles, to prevent any Russian reinforcement, was refused by KFOR commander General Mike Jackson.^[164]

In 2010, James Blunt described in an interview how his unit was given the assignment of securing Pristina during the advance of the 30,000-strong peacekeeping force and how the Russian army had moved in and taken control of the city's airport before his unit's arrival. Blunt shared a part in the difficult task of addressing the potentially violent international incident. According to Blunt's account there was a stand-off with the Russians, and NATO Supreme Commander Clark gave provisional orders to over-power them. Whilst these were questioned by Blunt, they were rejected by General Jackson, with the now famous line, "I'm not having my soldiers responsible for starting World War III."^[165]

In June 2000, arms trading relations between Russia and Yugoslavia were exposed, which led to retaliation and bombings of Russian checkpoints and area police stations. Outpost Gunner was established on a high point in the Preševo Valley by Echo Battery 1/161 Field Artillery in an attempt to monitor and assist with peacekeeping efforts in the Russian Sector. Operating under the support of ⅔ Field Artillery, 1st Armored Division, the Battery was able to successfully deploy and continuously operate a Firefinder Radar system, which allowed the NATO forces to keep a closer watch on activities in the Sector and the Preševo Valley. Eventually a deal was struck whereby Russian forces operated as a unit of KFOR but not under the NATO command structure.^[166]

Because of the country's restrictive media laws, the Yugoslav media carried little coverage of events in Kosovo, and the attitude of other countries to the humanitarian disaster that was occurring there. Thus, few members of the Yugoslav public expected NATO intervention, instead thinking that a diplomatic agreement would be reached.^[167]

Support for the Kosovan War and, in particular, the legitimacy of NATO's bombing campaign came from a variety of sources. In a 2009 article, David Clark claimed "Every member of NATO, every EU country, and most of Yugoslavia's neighbours, supported military action."^[168] Statements from the leaders of United States, Czech Republic and United Kingdom, respectively, described the war as one "upholding our values, protecting our interests, and advancing the cause of peace",^[169] "the first war for values"^[168] and one "to avert what would otherwise be a humanitarian disaster in Kosovo."^[170] Others included the then UN Secretary General Kofi Annan who was reported by some sources as acknowledging that the NATO action was legitimate^[171] who emphasised that there were times when the use of force was legitimate in the pursuit of peace^[172] though Annan stressed that the "[UN Security] Council should have been involved in any decision to use force."^[172] The distinction between the legality and legitimacy of the intervention was further highlighted in two separate reports. One was conducted by the Independent International Commission on Kosovo, entitled The Kosovo Report,^[173] which found that:

It concluded that "the NATO military intervention was illegal but legitimate",^[174] The second report was published by the NATO Office of Information and Press^[175] which reported that, "the human rights violations committed on a large scale in Kosovo provide an incontestable ground with reference to the humanitarian aspect of NATO's intervention."^[176] Some critics note that NATO did not have the backing of the United Nations Security Council meant that its intervention had no legal basis, but according to some legal scholars, "there are nonetheless certain bases for that action that are not legal, but justified."^[171]

Aside from politicians and diplomats, commentators and intellectuals also supported the war. Michael Ignatieff called NATOs intervention a "morally justifiable response to ethnic cleansing and the resulting flood of refugees, and not the cause of the flood of refugees"^[177] while Christopher Hitchens said NATO intervened only, "when Serbian forces had resorted to mass deportation and full-dress ethnic "cleansing."^[178] Writing in The Nation, Richard A. Falk wrote that, "the NATO campaign achieved the removal of Yugoslav military forces from Kosovo and, even more significant, the departure of the dreaded Serbian paramilitary units and police"^[179] while an article in The Guardian wrote that for Mary Kaldor, Kosovo represented a laboratory on her thinking for human security, humanitarian intervention and international peacekeeping, the latter two which she defined as, "a genuine belief in the equality of all human beings; and this entails a readiness to risk lives of peacekeeping troops to save the lives of others where this is necessary."^[180] Reports stated there had been no peace between Albanians and Serbs, citing the deaths of 1,500 Albanians and displacement of 270,000 prior to NATO intervention.^[168]

Some criticised the NATO intervention as a political diversionary tactic, coming as it did on the heels of the Monica Lewinsky scandal, pointing to the fact that coverage of the bombing directly replaced coverage of the scandal in US news cycles.^[181] Also, some point out that before the bombing, rather than there being an unusually bloody conflict, the KLA was not engaged in a widespread civil war against Yugoslav forces and the death toll among all concerned (including ethnic Albanians) skyrocketed following NATO intervention.^[181] In a post-war report released by the Organization for Security and Co-operation in Europe, the organization also noted "the pattern of the expulsions and the vast increase in lootings, killings, rape, kidnappings and pillage once the NATO air war began on March 24".^[182]

US President Clinton, his administration and NATO governments were accused of inflating the number of Kosovo Albanians killed by state forces.^[183][184] The media watchdog group Accuracy in Media charged the alliance with distorting the situation in Kosovo and lying about the number of civilian deaths in order to justify U.S. involvement in the conflict.^[185]

After the bombing of the Chinese embassy in Belgrade, Chinese President Jiang Zemin said that the US was using its economic and military superiority to aggressively expand its influence and interfere in the internal affairs of other countries. Chinese leaders called the NATO campaign a dangerous precedent of naked aggression, a new form of colonialism, and an aggressive war groundless in morality or law. It was seen as part of a plot by the US to destroy Yugoslavia, expand eastward and control all of Europe.^[186]

The United Nations Charter does not allow military interventions in other sovereign countries with few exceptions which, in general, need to be decided upon by the United Nations Security Council; this legal enjoinment has proved controversial with many^{[171][173][174]} legal scholars who argue that though the Kosovo War was illegal, it was still legitimate. The issue was brought before the UN Security Council by Russia, in a draft resolution which, inter alia, would affirm "that such unilateral use of force constitutes a flagrant violation of the United Nations Charter". China, Namibia, and Russia voted for the resolution, the other members against, thus it failed to pass.^[187]

The war inflicted many casualties. Already by March 1999, the combination of fighting and the targeting of civilians had left an estimated 1,500–2,000 civilians and combatants dead.^[188] However, estimates showed that prior to the bombing campaign on March 24, 1999, approximately 1,800 civilians had been killed in the Kosovo war, mostly Albanians but also Serbs and that there had been no evidence of genocide or ethnic cleansing.^[189] By November 1999, 2,108 victims had been exhumed from the province with a total approaching 3,000 expected, but it was unclear how many were civilians and combatants, while the number was also far from the 10,000 minimum civilian death figure cited by Western officials.^[190] Final estimates of the casualties are still unavailable for either side.

Perhaps the most controversial deliberate attack of the war was that made against the headquarters of RTS, Serbian public radio and television, on April 23, 1999, which killed at least fourteen people.^[191]

Privately NATO European members were divided about the aims and necessity of the war.^[192] Most European allies did not trust the motives of Kosovan Albanians and according to NATO General Wesley Clark, "There was a sense among some that NATO was fighting on the wrong side" in a war between Christians and Muslims.^[192]

By contrast, Susan Sontag, who witnessed the 3-year long siege of Sarajevo, said that the NATO intervention came "eight years too late" and that Milosevic should have been stopped already during the bombing of Dubrovnik in 1991.^[193]

The Democratic League of Kosovo (DLK) led by Ibrahim Rugova had been the leading political entity in Kosovo since its creation in 1989. Its parallel government in exile was led by Bujar Bukoshi, and its Minister of Defence until 1998 was the former Yugoslav colonel Ahmet Krasniqi.^[194] DLK politicians opposed the armed conflict and were not ready to accept KLA as a political factor in the region and tried to persuade the population not to support it.^[195] At one point Rugova even claimed that it was set up by Serbian intelligence as an excuse to invade,^[196] or to discredit DLK itself.^[197] Nevertheless, the support for KLA even within DLK membership and specifically in the diaspora grew, together with the dissatisfaction with and antagonism toward DLK.^[198] KLA initial personnel were members or former members of the DLK.^[197][199] With the changes of the international stance towards KLA and its recognition as a factor in the conflict, DLK's position also shifted. The Armed Forces of the Republic of Kosovo, known as FARK, were established in order to place DLK as a military factor in addition to a political one. A parallel paramilitary structure such as FARK was not received well by the KLA.

On 21 September 1998 Ahmet Krasniqi was shot in Tirana.^[200] Those responsible were not found, although several theories emerged. The Democratic Party of Albania and its leader Sali Berisha, strong supporters of DLK and FARK, accused SHIK and the Albanian government, which was supporting the KLA,^[201] as the responsible parties.^[200] FARK was never a determining factor in the war and was not involved in any battles. It did not number more than few hundred men, and it did not show any commitment to fighting the Serbs, accepting a broader autonomy as a solution rather than independence.^[200] Some of the FARK officers were incorporated later under the KLA umbrella.^[202] Besides FARK, DLK would also politically and diplomatically oppose KLA and their methods. In a meeting with US President Clinton on 29 May 1999,^[203] Rugova, accompanied by Fehmi Agani, Bukoshi, and Veton Surroi, accused KLA of being a left-wing ideology bearer, and some of its leaders as being "nostalgic to known communist figures, such as Enver Hoxha",^[204] referring to the People's Movement of Kosovo (LPK) nucleus of KLA,^[205] an old underground rival with strong left-wing orientation.^[206][207]

Rugova was present at the negotiations held in Rambouillet and supported the Rambouillet Agreement since the first round, but without any influence.^[208] Following the NATO bombing of Yugoslavia and the massive ethnic cleansing of the Albanian population, there was a total Albanian support for the NATO campaign, including the DLK side. Surprisingly, Ibrahim Rugova showed up in Belgrade as a guest of Milosevic. At a joint TV appearance on April 1,^[209] ending in a Rugova-Milosevic handshake, Rugova asked for a peaceful solution and the bombings to stop.^[210][211] In the same conference, Millosevic presented his proposal for Kosovo as part of a three-unit federal Yugoslavian state. Rugova's presence in Belgrade scattered another set of accusations from KLA and its supporters. Besides being 'passive' and 'too peaceful', Rugova and DLK were accused as 'traitors'.^[212] Following Rugova's passage to Italy on May 5, Rugova claimed that he had been under duress and any "agreement" with Milosovic had no meaning.^[209] The general opinion was the DLK structures and its leader would vanish from the political scene of Kosovo after the Yugoslav withdrawal. Rugova himself stayed for several weeks out of Kosovo, while the prime-minister Bukoshi and other leading membership returned. But since only a fraction of Kosovo Albanians participated actively in the war, the support for DLK increased again as a way of opposing the arrogance of many KLA leaders who openly engaged in controlling the economical and political life within the vacuum created right before the deployment of UNMIK.^[213] In the October 2000 local elections, DLK was confirmed as the leading political party.^[214]

The feud between KLA and DLK continued in the post-war Kosovo. Many political activists of DLK were assassinated with the perpetrators not being found, including Xhemajl Mustafa, Rugova's most trusted aide.^[214]

In June 2000, the Red Cross reported that 3,368 civilians (mainly Kosovar Albanians, but with several hundred Serbs, and Roma) were still missing, nearly one year after the conflict, most of whom it concluded had to be 'presumed dead'.^[215]

A study by researchers from the Center for Disease Control and Prevention in Atlanta, Georgia published in 2000 in medical journal the Lancet estimated that "12,000 deaths in the total population" could be attributed to war.^[216] This number was achieved by surveying 1,197 households from February 1998 through June 1999. 67 out of the 105 deaths reported in the sample population were attributed to war-related trauma, which extrapolates to be 12,000 deaths if the same war-related mortality rate is applied to Kosovo's total population. The highest mortality rates were in men between 15 and 49 (5,421 victims of war) as well as for men over 50 (5,176 victims). For persons younger than 15, the estimates were 160 victims for males and 200 for females. For women between 15–49 the estimate is that there were 510 victims; older than 50 years the estimate is 541 victims. The authors stated that it was not "possible to differentiate completely between civilian and military casualties".

In the 2008 joint study by the Humanitarian Law Centre (an NGO from Serbia and Kosovo), The International Commission on Missing Persons, and the Missing Person Commission of Serbia made a name-by-name list of war and post-war victims. According to the updated 2015 Kosovo Memory Book, 13,535 people were killed or missing in Kosovo during the conflict, from 1 January 1998 up until December 2000. Of these, 10,812 were Albanians, 2,197 Serbs and 526 Roma, Bosniaks, Montenegrins and others. 10,317 civilians were killed or went missing, of whom 8,676 were Albanians, 1,196 Serbs and 445 Roma and others. The remaining 3,218 dead or missing were combatants, including 2,131 members of the KLA and FARK, 1,084 members of Serbian forces and 3 members of KFOR.^[24] As of 2019, the book had been updated to a total of 13,548.^[49] In August 2017, the UN High Commissioner for Human Rights reported that between 1998 and 1999, more than 6,000 people had gone missing in Kosovo, and that 1,658 remained missing, with neither the person nor the body having, at that time, been found.^[217]

Yugoslavia claimed that NATO attacks caused between 1,200 and 5,700 civilian casualties. NATO's Secretary General, Lord Robertson, wrote after the war that "the actual toll in human lives will never be precisely known" but he then offered the figures found in a report by Human Rights Watch as a reasonable estimate. This report counted between 488 and 527 civilian deaths (90 to 150 of them killed from cluster bomb use) in 90 separate incidents, the worst of which were the 87 Albanian refugees who perished at the hands of NATO bombs, near Koriša.^[218] Attacks in Kosovo overall were more deadly due to the confused situation with many refugee movements—the one-third of the incidents there account for more than half of the deaths.^[219]

Various estimates of the number of killings attributed to Yugoslav forces have been announced through the years. An estimated 800,000 Kosovo Albanians fled and an estimated 7,000 to 9,000 were killed, according to The New York Times.^[220] The estimate of 10,000 deaths is used by the US Department of State, which cited human rights abuses as its main justification for attacking Yugoslavia.^[221]

Statistical experts working on behalf of the International Criminal Tribunal for the former Yugoslavia (ICTY) prosecution estimate that the total number of dead is about 10,000.^[222] Eric Fruits, a professor at Portland State University, argued that the experts' analyses were based on fundamentally flawed data and that none of its conclusions are supported by any valid statistical analysis or tests.^[223]

In August 2000, the ICTY announced that it had exhumed 2,788 bodies in Kosovo, but declined to say how many were thought to be victims of war crimes.^[224] KFOR sources told Agence France Presse that of the 2,150 bodies that had been discovered up until July 1999, about 850 were thought to be victims of war crimes.^[225]

Known mass graves:

The KLA abducted and murdered Serbian, Roma, and moderate Albanian civilians during and after the war.^[227] The exact number of civilians killed by the KLA is not known, though estimates conducted in the initial post-war months listed several hundreds^[228][229] with the violence targeting the non-Albanian population intensifying in the immediate aftermath of KFOR deployment in the region.^[72] Although more than 2,500 non-Albanians are believed to have been killed in the period between January 1, 1998 and December 31, 2000, it is unclear how many of them were killed by the KLA or KLA affiliated groups.^[49]

Military casualties on the NATO side were light. According to official reports, the alliance suffered no fatalities as a direct result of combat operations. In the early hours of May 5, a US military AH-64 Apache helicopter crashed not far from the border between Serbia and Albania.^[230]

Another US AH-64 helicopter crashed about 40 miles (64 km) northeast of Tirana, Albania's capital, very close to the Albanian/Kosovo border.^[231] According to CNN, the crash happened 45 miles (72 km) northeast of Tirana.^[232] The two US pilots of the helicopter, Army Chief Warrant Officers David Gibbs and Kevin L. Reichert, died in that crash. They were the only NATO fatalities during the war, according to NATO official statements.

There were other casualties after the war, mostly due to land mines. During the war, the alliance reported the loss of the first US stealth aeroplane (an F-117 Nighthawk) ever shot down by enemy fire.^[233] Furthermore, an F-16 fighter was lost near Šabac and 32 unmanned aerial vehicles (UAVs) from different nations were lost.^[234] The wreckages of downed UAVs were shown on Serbian television during the war. Some US sources claim a second F-117A was also heavily damaged, and although it made it back to its base, it never flew again.^[235][236] A-10 Thunderbolts have been reported as losses, with two shot down^[29] and another two damaged.^[29] Three US soldiers riding a Humvee in a routine patrol were captured by Yugoslav special forces across the Macedonian border.^[26][237]

At first, NATO claimed to have killed 10,000 Yugoslav troops, while Yugoslavia claimed only 500; the NATO investigative teams later corrected it to a few hundred Yugoslav troops killed by air strikes.^[238] In 2001, the Yugoslav authorities claimed 462 soldiers were killed and 299 wounded by NATO airstrikes.^[239] Later, in 2013, Serbia claimed that 1,008 Yugoslav soldiers and policemen had been killed by NATO bombing.^[35] NATO initially claimed that 5,000 Yugoslav servicemen had been killed and 10,000 had been wounded during the NATO air campaign.^[36][37] NATO has since revised this estimate to 1,200 Yugoslav soldiers and policemen killed.^[38]

Of military equipment, NATO destroyed around 50 Yugoslav aircraft including 6 MiG-29s destroyed in air-to-air combat. A number of G-4 Super Galebs were destroyed in their hardened aircraft shelter by bunker-busting bombs which started a fire which spread quickly because the shelter doors were not closed. At the end of war, NATO officially claimed that they had destroyed 93 Yugoslav tanks. Yugoslavia admitted a total of 3 destroyed tanks. The latter figure was verified by European inspectors when Yugoslavia rejoined the Dayton accords, by noting the difference between the number of tanks then and at the last inspection in 1995. NATO claimed that the Yugoslav army lost 93 tanks (M-84's and T-55's), 132 APCs, and 52 artillery pieces.^[240] Newsweek, the second-largest news weekly magazine in the U.S, gained access to a suppressed US Air Force report that claimed the real numbers were "3 tanks, not 120; 18 armored personnel carriers, not 220; 20 artillery pieces, not 450".^[240][241] Another US Air Force report gives a figure of 14 tanks destroyed.^[39] Most of the targets hit in Kosovo were decoys, such as tanks made out of plastic sheets with telegraph poles for gun barrels, or old World War II–era tanks which were not functional. Anti-aircraft defences were preserved by the simple expedient of not turning them on, preventing NATO aircraft from detecting them, but forcing them to keep above a ceiling of 15,000 feet (4,600 metres), making accurate bombing much more difficult. Towards the end of the war, it was claimed that carpet bombing by B-52 aircraft had caused huge casualties among Yugoslav troops stationed along the Kosovo–Albania border. Careful searching by NATO investigators found no evidence of any such large-scale casualties.

The most significant loss for the Yugoslav Army was the damaged and destroyed infrastructure. Almost all military air bases and airfields (Batajnica, Lađevci, Slatina, Golubovci and Đakovica) and other military buildings and facilities were badly damaged or destroyed. Unlike the units and their equipment, military buildings could not be camouflaged. thus, defence industry and military technical overhaul facilities were also seriously damaged (Utva, Zastava Arms factory, Moma Stanojlović air force overhaul centre, technical overhaul centres in Čačak and Kragujevac). In an effort to weaken the Yugoslav Army, NATO targeted several important civilian facilities (the Pančevo oil refinery,^[242] Novi Sad oil refinery, bridges, TV antennas, railroads, etc.)

Around 1,500 Kosovo Liberation Army soldiers were killed, according to KLA's own estimates.^[23] HLC registered 2,131 KLA and FARK insurgents killed in its comprehensive database.^[24]

The Yugoslav and Serb forces caused the displacement of between 1.2 million^[70] to 1.45 million Kosovo Albanians.^[71] After the end of the war in June 1999, numerous Albanian refugees started returning home from neighboring countries. By November 1999, according to the UN High Commissioner for Refugees, 848,100 out of 1,108,913 had returned.^[243]

According to the 1991 Yugoslavia Census, of the nearly 2 million population of Kosovo in 1991, 194,190 were Serbs, 45,745 were Romani and 20,356 were Montenegrins.^[244] According to the Human Rights Watch, 200,000 Serbs and thousands of Roma fled from Kosovo during and after the war.^[245] A 2001 Human Rights Watch's report suggested that the removal of ethnic minorities in Kosovo was done in order to better justify an independent state, and there were over 1000 reports of beatings and torturing of minorities in Kosovo by ethnic Albanians in 2000 after the war finished.^[246] Homes of minorities were burned and Orthodox churches and monasteries were destroyed in the immediate aftermath of KFOR's arrival in Kosovo.^[246] Attackers combined this destruction with killings, harassment and intimidation designed to force people from their homes and communities.^[246] The Yugoslav Red Cross had also registered 247,391 mostly Serbian refugees by November. More than 164,000 Serbs left Kosovo during the seven weeks which followed Yugoslav and Serb forces' withdrawal from, and the NATO-led Kosovo Force (KFOR) entering Kosovo.^[247]

Further inter-ethnic violence took place in 2000, and 2004.

For the government of Serbia, cooperation with the International Criminal Tribunal for the Former Yugoslavia is "still regarded as a distressing obligation, the necessary price for joining the European Union".^[248] Religious objects were damaged or destroyed. Of the 498 mosques in Kosovo that were in active use, the International Criminal Tribunal for the former Yugoslavia (ICTY) documented that 225 mosques sustained damage or destruction by the Yugoslav Serb army.^[249] In all, eighteen months of the Yugoslav Serb counterinsurgency campaign between 1998-1999 within Kosovo resulted in 225 or a third out of a total of 600 mosques being damaged, vandalised, or destroyed.^[250][251] During the war, Islamic architectural heritage posed for Yugoslav Serb paramilitary and military forces as Albanian patrimony with destruction of non-Serbian architectural heritage being a methodical and planned component of ethnic cleansing in Kosovo.^[251][252]

Widespread rape and sexual violence by the Serbian army, police and paramilitaries occurred during the conflict and the majority of victims were Kosovo Albanian women,^[253][254] numbering an estimated 20,000.^[255] The crimes of rape by the Serb military, paramilitary and police amounted to crimes against humanity and a war crime of torture.^[253]

Yugoslav President Slobodan Milošević was charged by the UN's International Criminal Tribunal for the Former Yugoslavia (ICTY) with crimes against humanity and war crimes. In 2001, then-President Vojislav Koštunica "fought tooth and nail" against attempts to put Milošević before an international court but was unable to prevent this happening after further atrocities were revealed.^[256]

By 2014, the ICTY issued final verdicts against the indicted Yugoslav officials who were found guilty of deportation, other inhumane acts (forcible transfer), murder and persecutions (crimes against humanity, Article 5), as well as murder (violations of the laws or customs of war, Article 3):

The ICTY legally found that:

The ICTY also leveled indictments against KLA members Fatmir Limaj, Haradin Bala, Isak Musliu, and Agim Murtezi for crimes against humanity. They were arrested on February 17 and 18, 2003. Charges were soon dropped against Agim Murtezi as a case of mistaken identity and Fatmir Limaj was acquitted of all charges on November 30, 2005 and released. The charges were in relation to the prison camp run by the defendants at Lapušnik between May and July 1998.

In 2008, Carla Del Ponte published a book in which she alleged that, after the end of the war in 1999, Kosovo Albanians were smuggling organs of between 100 and 300 Serbs and other minorities from the province to Albania.^[260]

In March 2005, a UN tribunal indicted Kosovo Prime Minister Ramush Haradinaj for war crimes against the Serbs. On March 8, he tendered his resignation. Haradinaj, an ethnic Albanian, was a former commander who led units of the Kosovo Liberation Army and was appointed Prime Minister after winning an election of 72 votes to three in the Kosovo's Parliament in December 2004. Haradinaj was acquitted on all counts along with fellow KLA veterans Idriz Balaj and Lahi Brahimaj. The Office of the Prosecutor appealed their acquittals, resulting in the ICTY ordering a partial retrial. On 29 November 2012 all three were acquitted for the second time on all charges.^[261] The trials were rife with accusations of witness intimidation, as media outlets from several different countries wrote that as many as nineteen people who were supposed to be witnesses in the trial against Haradinaj were murdered (the ICTY disputed these reports).^[262]

According to Human Rights Watch (HRW), "800 non-Albanian civilians were kidnapped and murdered from 1998 to 1999". After the war, "479 people have gone missing ... most of them Serbs".^[263] Albanians accused of "collaboration" with Serbian authorities were also beaten, abducted, or killed, notably in the municipalities of Prizren, Djakovica, and Klina.^[264] HRW notes that "the intent behind many of the killings and abductions that have occurred in the province since June 1999 appears to be the expulsion of Kosovo's Serb and Roma population rather than a desire for revenge alone. In numerous cases, direct and systematic efforts were made to force Serbs and Roma to leave their homes."^[265] Some 200,000 Serbs and Roma fled Kosovo following the withdrawal of Yugoslav forces.^[266]

In April 2014, the Assembly of Kosovo considered and approved the establishment of a special court to try cases involving crimes and other serious abuses committed in 1999-2000 by members of the KLA.^[267] Reports of abuses and war crimes committed by the KLA during and after the conflict include massacres of civilians, prison camps, burning and looting of homes and destruction of medieval churches and monuments.^[268]

The Yugoslav government and a number of international pressure groups (e.g., Amnesty International) claimed that NATO had carried out war crimes during the conflict, notably the bombing of the Serbian TV headquarters in Belgrade on April 23, 1999, where 16 people were killed and 16 more were injured. Sian Jones of Amnesty stated, "The bombing of the headquarters of Serbian state radio and television was a deliberate attack on a civilian object and as such constitutes a war crime".^[269] A later report conducted by the ICTY entitled Final Report to the Prosecutor by the Committee Established to Review the NATO Bombing Campaign Against the Federal Republic of Yugoslavia concluded that, "Insofar as the attack actually was aimed at disrupting the communications network, it was legally acceptable" and that, "NATO's targeting of the RTS building for propaganda purposes was an incidental (albeit complementary) aim of its primary goal of disabling the Serbian military command and control system and to destroy the nerve system and apparatus that keeps Milosević in power."^[147] In regards to civilian casualties, it further stated that though they were, "unfortunately high, they do not appear to be clearly disproportionate."^[147]

The Kosovo War had a number of important consequences in terms of the military and political outcome. The status of Kosovo remains unresolved; international negotiations began in 2006 to determine Kosovo's level of autonomy as envisaged under UN Security Council Resolution 1244, but efforts failed. The province is administered by the United Nations despite its unilateral declaration of independence on February 17, 2008.

The UN-backed talks, led by UN Special Envoy Martti Ahtisaari, had begun in February 2006. Whilst progress was made on technical matters, both parties remained diametrically opposed on the question of status itself.^[295] In February 2007, Ahtisaari delivered a draft status settlement proposal to leaders in Belgrade and Pristina, the basis for a draft UN Security Council Resolution which proposes "supervised independence" for the province, which is in contrary to UN Security Council Resolution 1244. By July 2007, the draft resolution, which was backed by the United States, United Kingdom, and other European members of the Security Council, had been rewritten four times to try to accommodate Russian concerns that such a resolution would undermine the principle of state sovereignty.^[296] Russia, which holds a veto in the Security Council as one of five permanent members, stated that it would not support any resolution which is not acceptable to both Belgrade and Priština.^[297]

The campaign exposed significant weaknesses in the US arsenal, which were later addressed for the Afghanistan and Iraq campaigns. Apache attack helicopters and AC-130 Spectre gunships were brought up to the front lines but were never used after two Apaches crashed during training in the Albanian mountains. Stocks of many precision missiles were reduced to critically low levels. For combat aircraft, continuous operations resulted in skipped maintenance schedules, and many aircraft were withdrawn from service awaiting spare parts and service.^[298] Also, many of the precision-guided weapons proved unable to cope with Balkan weather, as the clouds blocked the laser guidance beams. This was resolved by retrofitting bombs with Global Positioning System satellite guidance devices that are immune to bad weather. Although pilotless surveillance aircraft were extensively used, often attack aircraft could not be brought to the scene quickly enough to hit targets of opportunity. This led missiles being fitted to Predator drones in Afghanistan, reducing the "sensor to shooter" time to virtually zero.

Kosovo also showed that some low-tech tactics could reduce the impact of a high-tech force such as NATO; the Milošević government cooperated with Saddam Hussein's Ba'athist regime in Iraq, passing on many of the lessons learned.^[299] The Yugoslav army had long expected to need to resist a much stronger enemy, either Soviet or NATO, during the Cold War and had developed effective tactics of deception and concealment in response. These would have been unlikely to have resisted a full-scale invasion for long, but were probably used to mislead overflying aircraft and satellites. Among the tactics used were:

As a result of the Kosovo War, the North Atlantic Treaty Organisation created a second NATO medal, the NATO Medal for Kosovo Service, an international military decoration. Shortly thereafter, NATO created the Non-Article 5 Medal for Balkans service to combine both Yugoslavian and Kosovo operations into one service medal.^[302]

Due to the involvement of the United States armed forces, a separate US military decoration, known as the Kosovo Campaign Medal, was established by President Bill Clinton in 2000.

The Kosovo Campaign Medal (KCM) is a military award of the United States Armed Forces established by Executive Order 13154 of President Bill Clinton on May 3, 2000. The medal recognises military service performed in Kosovo from March 24, 1999 through December 31, 2013.

A variety of weapons were used by the Yugoslav security forces and the Kosovo Liberation Army, NATO only operated aircraft and naval units during the conflict.

The weapons used by Yugoslav government were mostly Yugoslav made, while almost all of their AA units were Soviet made.

The weapons used by the Kosovo Liberation Army were mostly Soviet Kalashnikovs and Chinese derivatives of the AK-47 and some Western weaponry.

Aircraft used by NATO were:

Guided missiles used were: