The relations between the Greek and the Turkish states have been marked by alternating periods of mutual hostility and reconciliation ever since Greece won its independence from the Ottoman Empire in 1832. Since then the two countries have faced each other in four major wars—the Greco-Turkish War (1897), the First Balkan War of 1912 to 1913, the First World War (1914 to 1918) and finally the Greco-Turkish War (1919–22), which were followed by the Greco-Turkish population exchange and a period of friendly relations in the 1930s and 1940s. Both countries entered NATO in 1952. Relations deteriorated again in the 1950s due to the Cyprus issue, the 1955 Istanbul pogrom and the expulsion of the Istanbul Greeks in the 1960s, the Turkish invasion of Cyprus in 1974, and subsequent military confrontations over the Aegean dispute. A period of relative normalization began after 1999 with the so-called "earthquake diplomacy", which notably led to a change in the previously firmly negative stance of the Greek government on the issue of the accession of Turkey to the European Union.

In 1048 conflicts between Seljuqs and Byzantines (Greeks were dominant nation of the Byzantine Empire and the Empire was Hellenized) started. Many wars and battles were fought between the Byzantine and the Seljuq armies. Also, in 1300 conflicts between Ottomans and Byzantines started too.

In 1453, Ottomans conquered Constantinople, the capital city of the Byzantine Empire. In 1460 they conquered the Despotate of the Morea, in 1461 the Empire of Trebizond, in 1475 the Principality of Theodoro and by 1500 most of the plains and islands were in Ottoman hands. Holdouts included Rhodes, conquered in 1522, Cyprus in 1571, Crete, retained by the Venetians until 1669, and the Ionian islands which remained primarily under the rule of the Republic of Venice.

During the Ottoman–Venetian Wars and the Russo-Turkish War (1768–74) Greece provided aid to Ottoman rivals. Dionysius the Philosopher additionally organised several uprisings. In addition, the Lambros Katsonis fleet began harassing the Ottoman fleet in the Aegean Sea.

In 1770, the Ottoman army invaded the Mani.

In the 1803, 1807 and 1815 the Ottoman army invaded Mani. Also during this period, in 1803 there was a final fight between the Souliotes and the local Ottoman ruler, Ali Pasha, which ended the many years of conflicts between them.

In March 1821, the Greek War of Independence from the Ottoman Empire began. The Greeks formally declared their independence in January 1822, and after the Battle of Navarino in 1827, the establishment of a Greek state was recognized in the London Protocol of 1828. The first borders of the Greek state consisted of the Greek mainland south of a line from Arta to Volos plus Euboea and the Cyclades islands in the Aegean Sea. The rest of the Greek-speaking lands, including Crete, Cyprus and the rest of the Aegean islands, Epirus, Thessaly, Macedonia and Thrace, remained under Ottoman rule. Over one million Greeks also lived in what is now Turkey, mainly in the Aegean region of Asia Minor, especially around Smyrna, in the Pontus region on the Black Sea coast, in the Gallipoli peninsula, in Cappadocia, in Istanbul, in Imbros and in Tenedos.

Greek politicians of the 19th century were determined to include all these territories within a greatly enlarged single Greek state, based on the Byzantine model and with Constantinople (Istanbul) as its capital. This policy was called the Great Idea (Megali Idea). Constantinople had been the capital of the Eastern half of the Roman Empire until its fall to the Turks in 1453. The Ottomans naturally opposed these plans for a larger Greek state. The Empire was considered by the European powers as 'the sick man of Europe', but since these powers were irreconcilably divided over the fate of the Ottoman lands, the conflicts both reduced its territorial hold but also kept delaying its collapse.

During the Crimean War (1854 to 1856), Britain and France restrained Greece from attacking the Ottomans by occupying Piraeus. They were again prevented from taking military action during the Russo-Turkish War of 1877, in which the Greeks were keen to join in with the objective of territorial expansion, but Greece was unable to take any effective part in the war. Nevertheless, after the Congress of Berlin, in 1881 Greece was given most of Thessaly and part of Epirus. Also, in 1854-1896, there were revolts in the Ottoman Empire by the Greek population in Thessaly, Macedonia, Epirus.

In 1858-1896 there were many revolts in Crete, Thessaly Macedonia and Epirus against the Ottoman Empire by the Greek population.

In 1897, a new revolt in Crete led to the first Greco-Turkish War. An unprepared Greek army was unable to dislodge the Ottoman troops from their fortifications along the northern border, and with the resulting Ottoman counter-attack, the war resulted in minor territorial losses for Greece.

The Young Turks, who seized power in the Ottoman Empire in 1908, were Turkish nationalists whose objective was to create a strong, centrally governed state. The Christian minorities of the Empire, including Greeks, saw their position in the Empire deteriorate.

The First Balkan War of 1912–1913 was a direct consequence of the mounting tension, as a result of which Greece seized Crete, the islands, the rest of Thessaly and Epirus, and coastal Macedonia from the Ottomans, in alliance with Serbia and Bulgaria. Crete was once again the flashpoint for tension between the two nations

In 1913 an organized persecution of the Christian population of the Ottoman Empire, including the Greeks, was started. Greece entered the First World War in 1917 with the intention of seizing Constantinople (Istanbul) and Smyrna (İzmir) from the Ottomans, with the encouragement of Britain and France, who also promised the Greeks Cyprus at a certain stage. The ongoing genocide of Pontic Greeks in the Ottoman Empire also played a factor in this decision. Although there was little direct fighting between Greeks and Turks, when the Ottoman Empire collapsed in 1918 the Greeks were quick to claim the lands the Allies had promised them. The 1920 Treaty of Sèvres gave Greece eastern Thrace and an area of about 17,000 km² in western Anatolia around Smyrna. This Treaty was signed by the Ottoman government but never went into force, not having been ratified by Parliament.

Greece occupied Smyrna/İzmir on 15 May 1919, while Mustafa Kemal Pasha (later Atatürk), who was to become the leader of the Turkish opposition to the Treaty of Sèvres, landed in Samsun on May 19, 1919, an action that is regarded as the beginning of the Turkish War of Independence. He united the protesting voices in Anatolia and set in motion a nationalist movement to repel the armies that had occupied Turkey (including Italy, France and Britain) and establish new borders for a sovereign Turkish nation. Having created a separate government in Ankara, Kemal's government did not recognise the abortive Treaty of Sèvres and fought to have it revoked. The Greek advances into Anatolia were eventually checked and the Greek army was forced into retreat.

The Turkish army entered Smyrna/İzmir on 9 September 1922, effectively ending the Greco-Turkish War (1919-1922) in the field. The Greek army and administration had already left by sea. The war was put to an end by the Armistice of Mudanya, and the Treaty of Lausanne (1923) replaced previous treaties to constitute modern Turkey.

The Treaty of Lausanne (1923) also provided for a Population exchange between Greece and Turkey that had begun before the final signature of the treaty in July 1923. About one and a half million Greeks had to leave Turkey for Greece and about half a million Turks had to leave Greece for Turkey (note that the population exchange was on religious grounds, thus the exchange was officially that of Christians for Muslims). The exceptions to the population exchange were Istanbul (Constantinople) and the islands of Gökçeada (Imbros) and Bozcaada (Tenedos), where the Greek minority (including the Ecumenical Patriarch) was allowed to stay, and Western Thrace, whose Muslim minority was also allowed to stay.

Due to the defeat of the Greek army and the events following which terminated 3,000 years of Greek presence in Anatolia, Greece refers to it as the Asia Minor Catastrophe/Disaster. The alleged atrocities committed by the Greek army during the Greek occupation of Western Anatolia (1919–1922) left a lasting impression on the Turkish mind. Greek accusations, on the other hand, were focused on the Great Fire of Smyrna, especially in view of the account provided by George Horton, the U.S. Consul General in the city from 1919 to 1922.^[1] Horton's account remains as controversial as the fire itself.^[2][3]

The Treaty of Lausanne (1923) awarded the islands of Imbros and Tenedos to Turkey, under special provisions for the Greeks living there. Tenedos population was overwhelmingly Greek, and Imbros population was entirely Greek. However, after the legislation of "Civil Law" on 26 June 1927, the rights accorded to the Greek population of Imbros and Tenedos were revoked, in violation of the Lausanne Treaty. Thus, the island was demoted from an administrative district to a sub-district which resulted that the island was to be stripped of its local tribunals. Moreover, the members of the local council were obliged to have adequate knowledge of the Turkish language, which meant that the vast majority of the islanders were excluded. Furthermore, according to this law, the Turkish government retained the right to dissolve this council and in certain circumstances, to introduce police force and other officials who were non-islanders. This law also violated the educational rights of the local community and imposed an educational system similar to that followed by ordinary Turkish schools.^[4]

During the Corfu incident between Italy and Greece, at 1923, elements in Turkey advised Mustafa Kemal to seize the opportunity to invade Western Thrace.^[5]

The post-war leaders of Turkey and Greece, Kemal Atatürk and Eleftherios Venizelos respectively, were determined to establish normal relations between the two states. After years of negotiations, a treaty was concluded in 1930, and Venizelos made a successful visit to Istanbul and Ankara. Greece renounced all its claims over Turkish territory. This was followed by the Balkan Pact of 1934, in which Greece and Turkey joined Yugoslavia and Romania in a treaty of mutual assistance and settled outstanding issues (Bulgaria refused to join). Both leaders, recognising the need for peace resulted in more friendly relations, with Venizelos even nominating Atatürk for the Nobel Peace Prize in 1934.^[6]

In 1941, Turkey was the first country to send humanitarian aid to Greece to relieve the great famine in Athens during the Axis occupation. Turkish president İsmet İnönü signed a decision to help the people whose army he had personally fought during the Turkish War of Independence 19 years earlier. Foodstuffs were collected by a nationwide campaign of Kızılay (Turkish Red Crescent)and sent to the port of İstanbul to be shipped to Greece. The aid was shipped on board the vessel SS Kurtuluş with big symbols of the Red Crescent painted on both sides. (See SS Kurtuluş for more information.)

At the same time, Turkey signed a "Treaty of Friendship and cooperation" with Nazi Germany in June 1941.^[7] The following year, 1942, Turkey imposed the Varlık Vergisi, a special tax, which taxed the non-Muslim minorities of Turkey, including Greek minority. Also, during the WWII there was the incident of the Twenty Classes, this was the conscription of non-Muslims males who were sent in labour battalions.

The early Cold War brought closer the international policies of the two countries, in 1950 both fought at the Korean War at the side of the UN forces. In 1952, both countries joined NATO. In 1953 Greece, Turkey and Yugoslavia formed a new Balkan Pact for mutual defence against the Soviet Union.

A serious matter of conflict in Turkish-Greek relations since the 1950s has been Cyprus; at the time, it was a British colony with a Greek-Cypriot population share of 82% of the island's total. Some of the Greek Cypriots wanted unity (enosis) with Greece and, as early as 1931, there were nationalist riots in Nicosia. The Greek government was, due to its financial and diplomatic dependence on Britain, forced to disavow any aims for unification with Cyprus.

In the 1950s, the Cyprus issue flared up again when the Greek Cypriots, under Archbishop Makarios, claimed union with Greece, and the EOKA group launched a paramilitary movement on the island - mainly against the British, but also inflicting collateral damage to other parties and civilians. Eventually, Greek Prime Minister Alexander Papagos took the Cyprus issue to the United Nations.

Turkish nationalist sentiment, angered by the discrimination against the Turkish Cypriots, became inflamed at the idea that Cyprus would be ceded to Greece. This led to the Greek community of Istanbul becoming the target in the Istanbul Pogrom of 1955. In response, Greece withdrew from all co-operation with Turkey, which caused the Balkan Pact to collapse.

In 1960, a compromise solution to the Cyprus issue was agreed on: Britain granted independence to Cyprus, and a constitution was hammered out. Greek and Turkish troops were stationed on the island to protect their respective communities. Greek Prime Minister Constantine Karamanlis was the main architect of this plan, which led to an immediate improvement in relations with Turkey, particularly once Adnan Menderes was removed from power in Turkey.

During the period of intercommunal strife in 1963 and 1964, Greek and Turkish Cypriots were displaced and many were massacred on both sides.

On 30 December 1964, Makarios declared his proposal for a constitutional amendment that included 13 articles. Turkey, however, restated that she was against this and threatened war if Cyprus tried to achieve unity with Greece. In August, Turkish aircraft bombed Greek troops that surrounded a Turkish village (Erenkoy) and war seemed imminent. Once again, the Greek minority in Turkey suffered from the crisis, causing many Greeks to flee the country, and there were even threats to expel the Ecumenical Patriarch. Eventually, intervention by the United Nations led to another compromise solution.

In 1964 Turkish prime minister İsmet İnönü renounced the 1930 Greek-Turkish Treaty of friendship and took actions against the Greek minority.^[8][9] Turkey enforced strictly a long‐overlooked law barring Greek nationals from 30 professions and occupations, for example Greeks could not be doctors, nurses, architects, shoemakers, tailors, plumbers, cabaret singers, ironsmiths, cooks, tourist guides, etc.^[8] Many Greek have been ordered to give up their jobs after this law.^[10] 50,000 more Greeks were deported.^[11] They were given a week to leave the country. Deportees protested that it was impossible to sell businesses or personal property in so short of a time. Most of those deported were born in Turkey and they had no particular place to go in Greece.^[8] Greeks had difficulty getting credit at banks. Those expelled, in some cases, could not dispose of their property before leaving.^[10] Also, Turkey forcefully closed the Prinkipo Greek Orthodox Orphanage,^[12][13][14] the Patriarchate's printing house^[10] and the Greek minority schools on the islands of Gökçeada/Imbros^[15] and Tenedos/Bozcaada.^[16] Furthermore, the farm property of the Greeks on the islands was taken away from its owners.^[16] Moreover, university students were organizing boycotts against Greek shops.^[10] Teachers of schools maintained by the Greek minority complained of frequent “inspections” by squads of Turkish officers inquiring into matters of curriculum, texts and especially the use of the Greek language in teaching.^[10] Same year the Turkish Foreign Minister, Feridun Cemal Erkin, in an interview appeared to imply that the Dodecanese closest to Turkey's Asia Minor coast should have been turned over to Turkey to preserve Greek‐Turkish friendship.^[17]

The Cyprus dispute weakened the Greek government of George Papandreou and triggered, in April 1967, a military coup in Greece. Under the diplomacy of the military regime, there were periodic crises with Turkey, which suspected that the Greek regime was planning a pro-unification coup in Cyprus.

A 1971 Turkish law nationalized religious high schools and closed the Halki seminary on Istanbul's Heybeli Island which had trained Greek Orthodox clergy since 1844.

On July 15, 1974, a band of Greek Cypriot nationalists formed EOKA B, advocating Enosis (Union) with Greece and, backed by the Greek military junta in Athens, staged a coup against the Cypriot President and Archbishop Makarios. An ex-EOKA man, Nikos Sampson was appointed President. On July 20, Turkey—using its guarantor status arising from the trilateral accords of the 1959–1960 Zürich and London Agreement—invaded Cyprus without any resistance from the British forces based on the island, occupied 37% of the northern part and expelled the Greek population. Once again, war between Greece and Turkey seemed imminent, but actual war was averted when Sampson's coup collapsed a few days later and Makarios returned to power. Also, the Greek military junta in Athens, which failed to confront the Turkish invasion, fell from power on 24 July. The damage to Turkish-Greek relations was done, and the occupation of Northern Cyprus by Turkish troops would be a sticking point in Greco-Turkish relations for decades to come.

In 2018, declassified documents of the Communist Bulgaria revealed a plan to foment crisis between Turkey and Greece in 1971. The operation codenamed "Cross" and the plan was that Bulgarian secret agents would set fire to the Ecumenical Patriarchate of Constantinople and make it look like the work of Turks. The declassified documents state that “An intervention” in the religious entity would have “significantly damage[d] Turkish-Greek relations and force[d] the United States to choose one side in the ensuing crisis,”. In addition, the Bulgarians also planned to boost the effectiveness of its operation against Greece and Turkey by conducting “active measures" “for putting the enemy in a position of delusion." The plan was developed by the 7th Department of the First Main Directorate of the DS (intelligence and secret police services of communist Bulgaria) and was affirmed by Deputy Head of the Directorate on November 16, 1970, and approved by its Head. The operation was supposed to be prepared by the middle of 1971 and then executed, but it was abandoned.^[18][19]

Since the 1970s further issues arose between the two countries over sovereignty rights in the Aegean Sea. The Balkan Wars of 1913 had given Greece all the Aegean islands except Imbros and Tenedos, some of them only a few kilometres (barely more than three nautical miles) off the Turkish coast. Since the end of World War II, Turkish officials insisted that this led to questions regarding the delimitation of territorial waters, air space and other related zones of control. The conflict was motivated both by considerations of military tactical advantages and by questions of economic exploitation of the Aegean. The latter issue became particularly significant as after 1970 there were expectations of finding oil in the Aegean. This was highlighted during the crisis in 1987, when a Turkish ship was about to enter disputed waters to conduct an oil survey. The Greek Prime Minister of the time, Andreas Papandreou, ordered the ship to be sunk if found within disputed waters claimed by Greece. Consultations about this issue were held in Davos between the Greek and Turkish Prime Ministers.

Issues unresolved to this day concern the mutual delimitation of several zones of control:

The conflict over military flight activities has led to a practice of continuous tactical military provocations. Turkish aircraft regularly fly in the zones over which Greece claims control (i.e., the outer four miles of the claimed Greek airspace and the international parts of Athens FIR), while Greek aircraft constantly intercept them. Aircraft from both countries frequently engage in mock dogfights. These operations often cause casualties and losses for both the Greek and Turkish Air Forces.

In 1986, Turkish soldiers and Greek soldiers suffered casualties at the Evros River incident, due to fire exchange. Turkish and Greek soldiers have exchanged fire in the past, as Greeks have tried to stop Iranian refugees from entering the country illegally from Turkey, but this incident was the first in which there have been casualties. During this period, Greek soldiers along the border with Turkey were on alert after receiving reports that Turkey planned to help thousands of refugees slip into Greece illegally.

In 1987, the Sismik incident nearly started a war between Greece and Turkey.

During the Cyprus Missile Crisis, between early 1997 and late 1998, tensions continued between Greece and Turkey, due to Greece's support of the Cypriot position.

In 1999, Abdullah Öcalan, the leader of the Kurdistan Workers' Party, was captured by the Turkish Intelligence Service agents in Nairobi, Kenya, while leaving the Greek Embassy. Öcalan was carrying both Greek and Cypriot passports.^[38] Fearing a hostile Turkish reaction, three Greek ministers resigned: Foreign Minister Theodoros Pangalos, in charge of the attempt to hide Öcalan at the Greek Ambassador's residence in Kenya and to find him asylum; Interior Minister Alekos Papadopoulos, in charge of the Greek Intelligence Service involved in the operation; and Public Order Minister Philippos Petsalnikos, in charge of the Greek security forces which failed to stop the smuggling of Öcalan into Greece in January 1999.^[39]

Relations between Greece and neighbouring Turkey improved after successive earthquakes hit both countries in the summer of 1999. The so-called "earthquake diplomacy" generated an outpouring of sympathy and generous assistance provided by ordinary Greeks and Turks in both cases. These acts were encouraged from the top and took many foreigners by surprise, preparing the public for a breakthrough in bilateral relations, which had been marred by decades of hostility over anti-Greek pogroms, territorial disputes and the situation in the divided island of Cyprus.

Ten years later, Greece has become one of the key supporters of Turkey's struggle to enter the European Union. Yet, despite the confidence Greece and Cyprus have shown, voting YES for Turkey in order to begin its entry negotiations with the European Union in October 2005, many key issues remain unresolved. Furthermore, Turkey still denies access to Cypriot vessels to its territory, an obligation towards the EU with a 2006 deadline. The Turkish government counters that this restriction regarding Cypriot vessels was taken after the trade embargo decision against the portion of Cyprus illegally occupied by Turkey. The issue remains deadlocked, despite UN and EU attempts to mediate. Other unfulfilled obligations include Christian minority rights, acknowledgement of the Orthodox Church of Constantinople and the role of the Ecumenical Patriarch.

In 2002, Turkey and Greece made an unsuccessful attempt to jointly host the 2008 UEFA European Football Championship. The bid was one of the four candidacies that was recommended to the UEFA Executive Committee, the joint Austria/Switzerland bid winning the right to host the tournament.

A sign of improved relations was visible in the response to a mid-air collision by Greek and Turkish fighter jets in the southern Aegean in May 2006. While the Turkish pilot ejected safely, the Greek pilot lost his life. However, both countries agreed that the event should not affect their bilateral relations^[40] and made a strong effort to maintain them by agreeing to a set of confidence-building measures in the aftermath of the accident.

In December 2011, the Turkish newspaper Birgun reported on an interview with former Turkish prime minister Mesut Yilmaz saying that Turkey was behind a number of large forest fires in Greece in the 1990s. Yilmaz later denied the statements, saying he had been misquoted by the newspaper and that he had been actually referring to unsubstantiated reports of Greek involvement in Turkish forest fires.^[41][42] However, despite Yilmaz's denial, the allegations strained the relations between the two countries. Also, former head of Greek intelligence service said they had intelligence that Turkish agencies were involved in the arsons in the 1990s but had no proof. He said they had received information from their agents in Turkey that Turkish agents or others were involved in the forest fires on Greek islands.^[43]

Ιn August 2017, a Turkish citizen was arrested after trying to set a fire near a Greek highway in Xanthi. He had applied for political asylum in Greece.^[44]

Turkey is a transit point for illegal immigrants trying to reach Europe (as well as being a destination itself; see Immigration to Turkey for details). As a result of bilateral negotiations, a readmission agreement was signed between Turkey and Greece in November 2001 and went into effect in April 2002. For third-country nationals, this protocol gives the parties 14 days to inform each other of the number of persons to be returned after the date of illegal entry. For nationals of the two countries the authorities can make use of simplified procedures. But the strict application of the agreement is reported to have retrograded as of 2003. Incidents concerning illegal immigration are frequent on the border of the two countries. Turkey, which is a transit point for illegal immigrants trying to reach Europe, has been accused of not being able to secure its borders with Greece. Since 1996 40 illegal immigrants have been killed by mines, after entering Greek territory in Evros.^[45] In 2001, about 800 illegal immigrants were rescued by the Greek coast guard after a fire broke out on board the Turkish-flagged Brelner, believed to have set sail from the Turkish port of İzmir, probably en route to Italy.^[46] According to Greek sources the Turkish authorities are tolerant of smugglers trafficking illegal immigrants into Greece; a notable such incident is the one of a trafficking boat, filmed in September 14, 2009 by the Latvian helicopter crew of Frontex patrolling near Farmakonisi island, during which "it is clear that the Turkish coastguard, at best, does not prevent the "slavetrade" vessels to sail from its shores. At worst, it accompanies them into Greek territorial waters".^[47][48] The human trafficking into Greece through the Aegean Sea has been a documented, widespread phenomenon while "the failure, reported by Frontex, of Turkish officials to stop suspicious vessels as they leave, ensure that a steady stream of migrants reaches Lesbos and other islands in the Aegean".^[49]

On July, 2016, after the failed Turkish coup d'état attempt Greek authorities on a number of Aegean islands have called for emergency measures to curtail a growing flow of refugees from Turkey, the number of migrants and refugees willing to make the journey across the Aegean has increased noticeably after the failed coup. At Athens officials voiced worries because Turkish monitors overseeing the deal in Greece had been abruptly pulled out after the failed coup without being replaced.^[50][51][52] Also, the mayor of Kos, expressed concern in a letter to the Greek Prime Minister sighting the growing influx of refugees and migrants after the failed coup.^[53] The Association of Greek Tourism Enterprises (SETE) warned about the prospect of another flare-up in the refugee/migrant crisis due to the Turkish political instability.^[54]

In June 2018, Turkey suspended its bilateral migrant readmission deal with Greece in response to the decision by the Greeks to release the eight Turkish soldiers who fled to Greece after the 2016 Turkish coup d'état attempt.^[55] NATO Secretary-General Jens Stoltenberg has called for “restraint and calm” after Turkey's decision.^[56]

In August 2019, about 650 people reached Lesbos from the Turkish coast in one day. It was the first mass arrival from Turkey since the 2016 EU-Turkey deal on migrant crisis. The Greek Foreign Minister summoned the Turkish ambassador to "express Greece’s deep discontent". The Turkish ambassador said that Ankara was "committed" to the deal and that its policy had not changed after being asked how so many were managing to make it Greek shores. In the first two weeks of August 2019, 1,929 people arrived on Lesbos from Turkey, compared with 479 in the same period last year.^[57][58] Due to high influx of immigrants from Turkey into Greece in 2019, the Greek Minister for Civil Protection Michalis Chrysochoidis warned that a new migrant crisis, like the previous one, will repeat if the situation were to continue.^[59]

During the 2010 trial for an alleged plot to stage a military coup dating back to 2003, conspirators were accused of planning attacks on mosques, trigger a conflict with Greece by shooting down one of Turkey's own warplanes accusing Greeks for this and planting bombs in Istanbul to pave the way for a military takeover.^[60][61][62]

After 1996, Greek Foreign Minister, and later Prime Minister, George Papandreou charted a major change of direction in Greek–Turkish relations. He lifted Greece's objections to Turkey's EU aspirations and energetically supported Turkey's bid for EU candidate status.^[63]

A 2005 opinion poll showed that only 25% of the Greek public believed Turkey has a place in the European Union.^[64]

In September 2017, Greek Prime Minister, Alexis Tsipras, mentioned that halting accession talks with Turkey would be a strategic mistake by the European Union, amid a war of words raging between Germany and Turkey.^[65] Also, former Greek Prime Minister, George Papandreou, has urged European Union leaders to keep the doors open to Turkey and to continue dialogue with the Turkish government, in an apparent reference to German Chancellor Angela Merkel’s calls for the suspension of accession talks with Turkey.^[66]

In 2013, Greek authorities arrested four militants on two separate operations near the Greece-Turkey border, while the DHKP-C was about to organize an attack on Turkish soil.^[67]

In 2014, Greek authorities arrested a number of militants in several operations, including high-ranking members of the Turkish terrorist group.^[68]

In November 28, 2017, Greek police raided apartments in Athens and detained nine Turks (one woman and eight men), members of the DHKP-C, plotting to assassinate Recep Tayyip Erdoğan using rockets, during his visit to Greece.^[69]

In February 2018, a suspected member of the DHKP-C, against whom there was an Interpol red notice, was arrested while trying to enter into Greece. In June 2018, a Greek court ordered the extradition of this person to Turkey.^[70]

On June 21, 2017, Presidency of Religious Affairs (Diyanet) organized a special program, which included the recitation of the Quran and prayers in Hagia Sofia, to mark the Laylat al-Qadr, the program was broadcast live by state-run television TRT. On June 22, a Greek statement mentioned that Hagia Sophia is a UNESCO world heritage site and should not be any attempt to convert it into a mosque. On June 23 Turkey condemned the Greek statement.^[71]

In March 2019, Turkish President Erdoğan said that he will change the status of Hagia Sophia from a museum to a mosque,^[72] adding that it was a "very big mistake" to turn it into a museum.^[73]

In March 2018, Turkey detained two Greek military officers who crossed into Turkey, by mistake, while following the trail of suspected illegal migrants. Turkish courts have ordered their detention on suspicion of illegal entry and attempted military espionage. In April 2018, Greece said that Turkey appeared to be seeking some political leverage by continuing to hold the soldiers without trial for more than a month.^[74][75] In April, EU Commission President Jean-Claude Juncker said that the Turkish claim that the soldiers posed a threat is ridiculous.^[76] In addition, Turkish President Recep Tayipp Erdogan said he would consider releasing the soldiers if eight Turkish servicemen, who sought asylum in Greece following the failed 2016 coup attempt, were sent back to Turkey first. The Greek side has described this as "blackmail", with the Defence Ministry describing the soldiers as "hostages". Greek President said: "There was an unacceptable connection made between the Greek officers who were arbitrarily detained, and Turkish citizens who came to Greece and requested asylum. Because Greece implemented - I emphasize this - implemented international law, it was granted. These are two totally different cases and any confusion is unthinkable"^[77] In August 2018, the Turkish court ruled for the two soldiers' release, pending trial,^[78] adding that there were no reasons to kept them in pretrial detention.^[79] They are released and returned to Greece after being held for almost 6 months without any charges being pressed against them.^[80] Meanwhile, on 2 May 2018, a Turkish municipal worker was arrested after he illegally crossed to Greece near Kastanies. He stated that he accidentally crossed the border while carrying out construction work. In 5 May 2018, he returned to Turkey.^[81]

In September 9, 2018, two Turkish soldiers were arrested by Greek patrol units. According to the Turkey's General Staff, the soldiers were chasing irregular migrants when they crossed the border by mistake. The soldiers released and returned to Turkey the same day, after the Turkish side held talks with the Greek authorities.^[82] The Turkish defence Minister Hulusi Akar said that “positive and constructive attitude by the two countries gave out a good example of the neighbourly relations.”^[83]

Official relations between Greece and Turkey had improved, mainly due to the Greek government's supportive attitude towards Turkey's efforts to join the EU, although various issues have never been fully resolved and remain constant sources of conflict. An attempt at rapprochement, dubbed the Davos process, was made in 1988. The retirement of Greek Prime Minister Andreas Papandreou contributed to this improvement. His son, a foreign minister George Papandreou, made considerable progress in improving relations. He found a willing partner in Ismail Cem and later in the Turkish Prime Minister Recep Tayyip Erdoğan.

Turkey continues to systematically disregard Greek national sovereign territory by violating air and sea borders.^{[84][85][86][87][88][89][90][91]} In March 2015 the Turkish forces had intended to carry out a military exercise in the Aegean disrupting international air traffic, and restricted traffic around two Greek national airports.^[92][93][94] Turkey subsequently withdrew the earlier Notice to Airmen (NOTAM) reserving an extensive area of air space over the Aegean from March 2 to December 31, 2015. The Greek government lodged complaints with NATO, the European Union, the United Nations, and the International Civil Aviation Authority over this flashpoint and NATO was thought to have played a role de-escalating.^[95]

After the failed 2016 Turkish coup d'état attempt, several Turkish military personnel sought political asylum in Greece while Turkey requested their extradition. Also, the Greek armed forces and Coast Guard were on alert and increased the patrols and a contingent of the Greek Police was dispatched to some Greek islands to conduct checks there in order to prevent the arrival of participants in the failed coup to Greece and arrest anyone who might manage to enter the country.^[96][97][98]

Also, the two Turkish military attaches in Athens fled to Italy. The Greek Foreign Ministry cancelled the two attaches accreditations on August 7, 2016, upon the request of the Turkish Foreign Ministry. At August 11, 2016, the Turkish Foreign Minister Mevlut Cavusoglu said that they left Greece to Italy on August 6 and added that Turkey will officially ask Italian authorities to extradite the two soldiers.^[99][100]

On August 25, 2016, seven Turkish citizens were seeking asylum in Greece. A couple, both of whom are university professors, and their two children applied for asylum in Alexandroupoli after they illegally entered the country from the northeastern border. Also, three businessmen have illegally reached the Greek island of Rhodes, and they also applied for asylum.^[101][102]

On August 30, 2016, a Turkish judge arrived to the Greek island of Chios on a migrant boat and sought asylum in the country. He told the Greek coast guard and police officers that he is being persecuted in Turkey for his political beliefs by the government of President Tayyip Erdogan. The Turkish judge had been arrested for illegally entering the country and, also, he transferred to Athens for his asylum proceedings.^{[103][104][105][106]}

On September 21, 2016, ten Turkish civilians, two men, two women and six children landed by boat illegally on the Greek island of Rhodes and sought asylum. They told the Greek authorities they were working in the private sector in Turkey and they were being persecuted by the Turkish government due to their political beliefs.^[107][108]

On September 29, 2016, five Turkish nationals, a couple and their child and two other men, arrived in Alexandroupolis by crossing the Evros River by boat illegally and requested political asylum.^[109]

On 15 February 2017, five Turkish commandos illegally entered Greece through the Evros river. However, once they entered the country, the group split. Two of them surrendered to the police and on 20 February 2017, requested political asylum. The Greek government announced that the Greek authorities will not allow the country to be dragged into the ongoing feud between the Turkish state and the followers of Gulen.^[110][111] But there was no sign of the other three. According to a lawyer, there were indications that the other three had been arrested by Greek authorities who were about to expel them to Turkey. Later, according to new evidence and new information these three “arrested” marines were delivered under fast and informal procedures from Greek to Turkish services.^[112][113]

On October 24, 2017, Turkish authorities obtained information that 995 Turks have applied for asylum in Greece after the coup attempt.^[114]

More than 1,800 Turkish citizens requested asylum in Greece in 2017.^[115]

In August 2018, the former lawmaker for the Peopless Democratic Party, Leyla Birlik, requested asylum in Greece after illegally crossing the border near Alexandroupolis.^[116]

In 2016, Greece has named Turkey an “honorary country” together with Israel, Russia and the United States. Every year four countries are selected by Greece as “honorary” and their citizens enjoy additional benefits and discounts at Greece.^[117]

On August 15, 2016, the Greek President Prokopis Pavlopoulos accused Turkey that it unjustifiably closed the historic Greek Orthodox Sumela Monastery, which is dedicated to the Virgin Mary, in Turkey's Black Sea region during the celebrations for the Assumption of Virgin Mary/Dormition of the Mother of God. The Turkish Foreign Ministry responded to the Greek President that his remarks distorted the decision to temporarily close the Sumela Monastery do not comply with facts and imply demagogy far from the responsibility of a statesman.^[118]

On September 29, 2016, Turkish President Recep Tayyip Erdogan disputed Treaty of Lausanne. He said “We gave away the islands (in the Aegean) through the Treaty of Lausanne,”, “The islands, which if we care to shout (from the western Asia Minor coast) we’ll be heard on the other side (the islands), we gave away with Lausanne. What will now happen with the continental shelf? What will happen with the airspace and land? We’re still fighting for all of these". This caused displeasure in Athens. A Greek Foreign Ministry source remarked that “everyone should respect the Treaty of Lausanne,” noting that it is “a reality in the civilized world which no one, including Ankara, can ignore.”, added that the Turkish leader's comments were likely geared for domestic consumption.^{[119][120][113]}

On October 16, 2016, Turkish President Recep Tayyip Erdogan said, “We cannot draw boundaries to our heart, nor do we allow it,” and that “Turkey cannot disregard its kinsmen in Western Thrace, Cyprus, Crimea and anywhere else.” Greece saw his speaking as an effort, informed by a neo-Ottoman narrative and romantic irredentism, to dispute past agreements that settled the borders between the two countries. Greek Foreign Ministry said, on October 17, that "Thrace is Greek, democratic and European. Any other thought is unthinkable and dangerous,”^[121]

On March 27, 2017, the former editor in chief of the English version of the Turkish newspaper Zaman, Abdullah Bozkurt, posted a tweet on his account warning of increased clandestine operations of Turkish intelligence agents in Greece.^[122]

On August 16, 2017, Turkish Foreign Minister Mevlut Cavusoglu speaking before Turkey's National Assembly, said that a number of interconnected problems remain in the Aegean between the Turkey and Greece. “Among these problems is the question of sovereignty of certain islets and rocky formations, and the fact that there are no sea borders which are set by an international agreement between Turkey and Greece,” he said.^[123]

On August 22, 2017, the Erbakan Foundation (a religious foundation) at Sinop staged a protest, demanding the removal of a statue of the ancient Greek philosopher, who was born at Sinop, Diogenes from the city entrance. The foundation said it was protesting the fact that the Greek ideology being attached to the province.^[124]

In December 2017 Recep Tayyip Erdogan became the first Turkish president to visit Greece in 65 years.^[125] Also, the Republican People's Party (CHP) leader Kemal Kılıçdaroğlu in a speech at the parliament criticized Recep Tayyip Erdoğan over his "failure" to raise the issue of "18 occupied islands" during his visit to Greece. His political party also, declared the Turkish names of 156 islands, islets and reefs in the Aegean Sea and claimed them as Turkish territory. The Greek Defense minister, Panos Kammenos, responded "come and get it". Kılıçdaroğlu then said, that Turkey will come and take all of those islands back, while the CHP's deputy leader for foreign affairs, Öztürk Yılmaz, said that "Greece should not test our patience".^[126][127]

On April 10, 2018, Greek soldiers fired warning shots at Turkish helicopter approaching the island of Ro. The helicopter was flying at a very low altitude late at night with its navigation lights switched off.^[128]

In April 16, 2018, Turkish Prime Minister Binali Yıldırım said that in April 15, Greek citizens plant a Greek flag on an uninhabited rocky islet at the Aegean, but the Turkish coast guard removed the flag. In addition, urged the Greek government to refrain from “provocative moves” in the "disputed areas" of the Aegean Sea. The Greek government responded that there was no evidence indicating "violation of Greek territory" and labeled the claims as "totally provocative and reprehensible".^[129][130]

In September 2018, the Turkish Agriculture and Forestry Ministry warned Turkish fishers not to enter the territorial waters of Greece. “In order to prevent unwanted incidents and accidents, and to abstain from activities that would harm our country’s legal and political theses and ones which we would be unable to explain or defend,” after several complaints were handed to Turkey's Foreign Ministry saying Turkish fisher boats had entered Greece's territorial waters.^[131]

On March 14, Turkish president Recep Tayyip Erdogan, during an interview, said that whenever Greek military aircraft take off in the Aegean, Turkish jets will follow suit.^[132] The next day the Greek Ministry of Foreign Affairs issued a press release saying that "Turkey’s effort to equate the flights of Turkish military aircraft that violate Greece's national sovereignty with the identification and interception missions the Hellenic Air Force carries out in defense of national sovereignty, is completely unacceptable", adding that "Turkish military aircraft violate Greek national air space on an almost daily basis, including through low-altitude overflights of inhabited Greek islands. This is a practice that Greece systematically condemns and reports, both bilaterally as well as to the competent international bodies." The ministry also said that the legal status in the Aegean is "clear and fully enshrined" in International Law, "leaving no room for doubt".^[133][132] The Turkish Foreign Ministry spokesperson responded that Greece calling Turkey's flights over the Aegean Sea a “threat” is incompatible with alliance and good neighborly relations, adding that the Greek Foreign Ministry's statement was "odd" in both its timing and content.^[134]

On March 17, Turkish president Recep Tayyip Erdogan during a speech in İzmir along with Gray Wolves leader Devlet Bahceli, made a reference to the Asia Minor Catastrophe saying: "[...] Smyrna you that you throw the infidels in the sea and protect the helpless".^[135] This statement prompted the response of the Greek Ministry of Foreign Affairs, stating that "Greece is not going to be swept away in the instrumentalisation of foreign policy to serve domestic political expediencies, or use history with terms that are offensive to neighbouring countries. Such unacceptable references undermine the trust we hope to build between our countries and are not in line with the European perspective that the Turkish leadership claims to support."^[136]

On March 22, Turkish Defense Minister Hulusi Akar stated that Turkey "control(s) the sea and the seabed. The seas. The Black Sea, the Aegean, the Eastern Mediterranean which also includes Cyprus" adding that "these areas lie within our sphere of interest… we have the responsibility of ensuring peace and calm".^[137] The Greek Defense Minister Evangelos Apostolakis issued a statement saying that although Greece is "struggling" to defuse tension "Akar surprised us with something new, with things that are not based on reason" adding that "it is the principle of Greece that we respect international law and the treaties" and "when these principles are questioned, we have to be concerned".^[138]