The Workers' and Peasants' Red Army,^[1] frequently shortened to Red Army,^[2] was the army and the air force of the Russian Soviet Federative Socialist Republic and, after 1922, the Union of Soviet Socialist Republics. The army was established immediately after the 1917 October Revolution. The Bolsheviks raised an army to oppose the military confederations (especially the various groups collectively known as the White Army) of their adversaries during the Russian Civil War. Beginning in February 1946, the Red Army, along with the Soviet Navy, embodied the main component of the Soviet Armed Forces; taking the official name of "Soviet Army", until its dissolution in December 1991. The former official name Red Army continued to be used as a nickname by both sides throughout the Cold War.

The Red Army provided the largest land force in the Allied victory in the European theatre of World War II, and its invasion of Manchuria assisted the unconditional surrender of Imperial Japan. During operations on the Eastern Front, it accounted for 75–80% of casualties the Wehrmacht and Waffen-SS suffered during the war and ultimately captured the Nazi German capital, Berlin.^[7]

In September 1917, Vladimir Lenin wrote: "There is only one way to prevent the restoration of the police, and that is to create a people's militia and to fuse it with the army (the standing army to be replaced by the arming of the entire people)."^[8] At the time, the Imperial Russian Army had started to collapse. Approximately 23% (about 19 million) of the male population of the Russian Empire were mobilized; however, most of them were not equipped with any weapons and had support roles such as maintaining the lines of communication and the base areas. The Tsarist general Nikolay Dukhonin estimated that there had been 2 million deserters, 1.8 million dead, 5 million wounded and 2 million prisoners. He estimated the remaining troops as numbering 10 million.^[9]

While the Imperial Russian Army was being taken apart, "it became apparent that the rag-tag Red Guard units and elements of the imperial army who had gone over the side of the Bolsheviks were quite inadequate to the task of defending the new government against external foes." Therefore, the Council of People's Commissars decided to form the Red Army on 28 January 1918.^[3] They envisioned a body "formed from the class-conscious and best elements of the working classes." All citizens of the Russian republic aged 18 or older were eligible. Its role being the defense "of the Soviet authority, the creation of a basis for the transformation of the standing army into a force deriving its strength from a nation in arms, and, furthermore, the creation of a basis for the support of the coming Socialist Revolution in Europe." Enlistment was conditional upon "guarantees being given by a military or civil committee functioning within the territory of the Soviet Power, or by party or trade union committees or, in extreme cases, by two persons belonging to one of the above organizations." In the event of an entire unit wanting to join the Red Army, a "collective guarantee and the affirmative vote of all its members would be necessary."^[10][11] Because the Red Army was composed mainly of peasants, the families of those who served were guaranteed rations and assistance with farm work.^[12] Some peasants who remained at home yearned to join the Army; men, along with some women, flooded the recruitment centres. If they were turned away they would collect scrap metal and prepare care-packages. In some cases the money they earned would go towards tanks for the Army.^[13]

The Council of People's Commissars appointed itself the supreme head of the Red Army, delegating command and administration of the army to the Commissariat for Military Affairs and the Special All-Russian College within this commissariat.^[10] Nikolai Krylenko was the supreme commander-in-chief, with Aleksandr Myasnikyan as deputy.^[14] Nikolai Podvoisky became the commissar for war, Pavel Dybenko, commissar for the fleet. Proshyan, Samoisky, Steinberg were also specified as people's commissars as well as Vladimir Bonch-Bruyevich from the Bureau of Commissars. At a joint meeting of Bolsheviks and Left Socialist-Revolutionaries, held on 22 February 1918, Krylenko remarked: "We have no army. The demoralized soldiers are fleeing, panic-stricken, as soon as they see a German helmet appear on the horizon, abandoning their artillery, convoys and all war material to the triumphantly advancing enemy. The Red Guard units are brushed aside like flies. We have no power to stay the enemy; only an immediate signing of the peace treaty will save us from destruction."^[10]

The Russian Civil War (1917–1923) occurred in three periods:

At the start of the civil war, the Red Army consisted of 299 infantry regiments.^[17] The civil war intensified after Lenin dissolved the Russian Constituent Assembly (5–6 January 1918) and the Soviet government signed the Treaty of Brest-Litovsk (3 March 1918), removing Russia from the Great War. Free from international war, the Red Army confronted an internecine war against a variety of opposing anti-Communist forces, including the Revolutionary Insurrectionary Army of Ukraine, the "Black Army" led by Nestor Makhno, the anti-White and anti-Red Green armies, efforts to restore the defeated Provisional Government, monarchists, but mainly the White Movement of several different anti-socialist military confederations. "Red Army Day", 23 February 1918, has a two-fold historical significance: it was the first day of drafting recruits (in Petrograd and Moscow), and the first day of combat against the occupying Imperial German Army.^[18][4]

On 6 September 1918 the Bolshevik militias consolidated under the supreme command of the Revolutionary Military Council of the Republic (Russian: Революционный Военный Совет, romanized: Revolyutsionny Voyenny Sovyet (Revvoyensoviet)). The first chairman was Leon Trotsky, and the first commander-in-chief was Jukums Vācietis from the Latvian Riflemen; in July 1919 he was replaced by Sergey Kamenev. Soon afterwards Trotsky established the GRU (military intelligence) to provide political and military intelligence to Red Army commanders.^[19] Trotsky founded the Red Army with an initial Red Guard organization and a core soldiery of Red Guard militiamen and Chekist secret police.^[20] Conscription began in June 1918,^[21] and opposition to it was violently suppressed.^[22] To control the multi-ethnic and multi-cultural Red Army soldiery, the Cheka operated special punitive brigades which suppressed anti-communists, deserters, and "enemies of the state".^[19][23] Wartime pragmatism allowed the recruitment of ex-Tsarist officers and sergeants (non-commissioned officers, NCOs) into the Red Army.^[24] Lev Glezarov's special commission recruited and screened them. By mid-August 1920 the Red Army's former Tsarist personnel included 48,000 officers, 10,300 administrators, and 214,000 NCOs.^[25] At the civil war's start, ex-Tsarists made up 75% of the Red Army officer-corps,^[26] who were employed as military specialists (voenspetsy, ru:Военный советник).^[27] The Bolsheviks occasionally enforced the loyalty of such recruits by holding their families as hostages.^[26] When the civil war ended in 1922, ex-Tsarists constituted 83% of the Red Army's divisional and corps commanders.^[27]

The Red Army used special regiments for ethnic minorities, such as the Dungan Cavalry Regiment commanded by the Dungan Magaza Masanchi.^[28] The Red Army also co-operated with armed Bolshevik Party-oriented volunteer units, the Части особого назначения – ЧОН (special task units – chasti osobogo naznacheniya – or ChON) from 1919 to 1925.^[29]

The slogan "exhortation, organization, and reprisals" expressed the discipline and motivation which helped ensure the Red Army's tactical and strategic success. On campaign, the attached Cheka Special Punitive Brigades conducted summary field courts-martial and executions of deserters and slackers.^[23][30] Under Commissar Yan Karlovich Berzin the Special Punitive Brigades took hostages from the villages of deserters to compel their surrender; one in ten of those returning was executed. The same tactic also suppressed peasant rebellions in areas controlled by the Red Army, the biggest of these being the Tambov Rebellion.^[31] The Soviets enforced the loyalty of the various political, ethnic, and national groups in the Red Army through political commissars attached at the brigade and regimental levels. The commissars also had the task of spying on commanders for political incorrectness.^[32] Political commissars whose Chekist detachments retreated or broke in the face of the enemy earned the death penalty. In August 1918, Trotsky authorized General Mikhail Tukhachevsky to place blocking units behind politically unreliable Red Army units, to shoot anyone who retreated without permission.^[33] In 1942, during the Great Patriotic War (1941–1945) Joseph Stalin reintroduced the blocking policy and penal battalions with Order 227

The Red Army controlled by the Russian Soviet Federative Socialist Republic invaded and annexed non-Russian lands helping to create the Soviet Union.^[34]

The Soviet westward offensive of 1918–19 occurred at the same time as the general Soviet move into the areas abandoned by the Ober Ost garrisons. This merged into the 1919–1921 Polish–Soviet War, in which the Red Army reached central Poland in 1920, but then suffered a defeat there, which put an end to the war. During the Polish Campaign the Red Army numbered some 6.5 million men, many of whom the Army had difficulty supporting, around 581,000 in the two operational fronts, western and southwestern. Around 2.5 million men and women were immobilized in the interior as part of reserve armies.^[35]

The XI Congress of the Russian Communist Party (Bolsheviks) (RCP (b)) adopted a resolution on the strengthening of the Red Army. It decided to establish strictly organized military, educational and economic conditions in the army. However, it was recognized that an army of 1,600,000 would be burdensome. By the end of 1922, after the Congress, the Party Central Committee decided to reduce the Red Army to 800,000. This reduction necessitated the reorganization of the Red Army's structure. The supreme military unit became corps of two or three divisions. Divisions consisted of three regiments. Brigades as independent units were abolished. The formation of departments' rifle corps began.

After four years of warfare, the Red Army's defeat of Pyotr Nikolayevich Wrangel in the south^[36] in 1920^[37] allowed the foundation of the Union of Soviet Socialist Republics in December 1922. Historian John Erickson sees 1 February 1924, when Mikhail Frunze became head of the Red Army staff, as marking the ascent of the general staff, which came to dominate Soviet military planning and operations. By 1 October 1924 the Red Army's strength had diminished to 530,000.^[38] The list of Soviet Union divisions 1917–1945 details the formations of the Red Army in that time.

In the late 1920s and throughout the 1930s, Soviet military theoreticians – led by Marshal Mikhail Tukhachevsky – developed the deep-operations doctrine,^[39] a direct consequence of their experiences in the Polish-Soviet War and in the Russian Civil War. To achieve victory, deep operations envisage simultaneous corps- and army-size unit maneuvers of simultaneous parallel attacks throughout the depth of the enemy's ground forces, inducing catastrophic defensive failure. The deep-battle doctrine relies upon aviation and armor advances with the expectation that maneuver warfare offers quick, efficient, and decisive victory. Marshal Tukhachevsky said that aerial warfare must be "employed against targets beyond the range of infantry, artillery, and other arms. For maximum tactical effect aircraft should be employed en masse, concentrated in time and space, against targets of the highest tactical importance."^[40]

Red Army deep operations found their first formal expression in the 1929 Field Regulations, and became codified in the 1936 Provisional Field Regulations (PU-36). The Great Purge of 1937–1939 and the Purge of 1940–1942 removed many leading officers from the Red Army, including Tukhachevsky himself and many of his followers, and the doctrine was abandoned. Thus at the Battle of Lake Khasan in 1938 and in the Battle of Khalkhin Gol in 1939 (major border clashes with the Imperial Japanese Army), the doctrine was not used. Only in the Second World War did deep operations come into play.

The Red army was involved in armed conflicts in the Republic of China during the Sino-Soviet conflict (1929), the Soviet Invasion of Xinjiang (1934), when it was assisted by White Russian forces, and the Xinjiang rebellion (1937). The Red Army achieved its objectives; it maintained effective control over the Manchurian Chinese Eastern Railway, and successfully installed a pro-Soviet regime in Xinjiang.^[41]

The Winter War (Finnish: talvisota, Swedish: vinterkriget, Russian: Зи́мняя война́)^[5] was a war between the Soviet Union and Finland. It began with a Soviet offensive on 30 November 1939—three months after the start of World War II and the Soviet invasion of Poland, and ended on 13 March 1940 with the Moscow Peace Treaty. The League of Nations deemed the attack illegal and expelled the Soviet Union on 14 December 1939.^[46]

The Soviet forces led by Semyon Timoshenko had three times as many soldiers as the Finns, thirty times as many aircraft, and a hundred times as many tanks. The Red Army, however, had been hindered by Soviet leader Joseph Stalin's Great Purge of 1937, reducing the army's morale and efficiency shortly before the outbreak of the fighting.^[47] With over 30,000 of its army officers executed or imprisoned, most of whom were from the highest ranks, the Red Army in 1939 had many inexperienced senior officers.^{[48][49] []} Because of these factors, and high commitment and morale in the Finnish forces, Finland was able to resist the Soviet invasion for much longer than the Soviets expected. Finnish forces inflicted stunning losses on the Red Army for the first three months of the war while suffering very few losses themselves.^{[49] []}

Hostilities ceased in March 1940 with the signing of the Moscow Peace Treaty. Finland ceded 11% of its pre-war territory and 30% of its economic assets to the Soviet Union.^{[50] []} Soviet losses on the front were heavy, and the country's international reputation suffered.^{[50] []} The Soviet forces did not accomplish their objective of the total conquest of Finland but conquered significant territory along Lake Ladoga, Petsamo and Salla. The Finns retained their sovereignty and improved their international reputation, which bolstered their morale in the Continuation War.

In accordance with the Soviet-Nazi Molotov–Ribbentrop Pact of 23 August 1939, the Red Army invaded Poland on 17 September 1939, after the Nazi invasion on 1 September 1939. On 30 November the Red Army also attacked Finland, in the Winter War of 1939–1940. By autumn 1940, after conquering its portion of Poland, the Third Reich shared an extensive border with USSR, with whom it remained neutrally bound by their non-aggression pact and trade agreements. Another consequence of the Molotov-Ribbentrop Pact was the Soviet occupation of Bessarabia and Northern Bukovina, carried out by the Southern Front in June–July 1940 and Soviet occupation of the Baltic states (1940). These conquests also added to the border the Soviet Union shared with Nazi-controlled areas. For Adolf Hitler, the circumstance was no dilemma, because^[51] the Drang nach Osten ("Drive towards the East") policy secretly remained in force, culminating on 18 December 1940 with Directive No. 21, Operation Barbarossa, approved on 3 February 1941, and scheduled for mid-May 1941.

When Germany invaded the Soviet Union in June 1941, in Operation Barbarossa, the Red Army's ground forces had 303 divisions and 22 separate brigades (5.5 million soldiers) including 166 divisions and brigades (2.6 million) garrisoned in the western military districts.^[52][53] The Axis forces deployed on the Eastern Front consisted of 181 divisions and 18 brigades (3 million soldiers). Three Fronts, the Northwestern, Western, and Southwestern conducted the defense of the western borders of the USSR. In the first weeks of the Great Patriotic War the Wehrmacht defeated many Red Army units. The Red Army lost millions of men as prisoners and lost much of its pre-war matériel. Stalin increased mobilization, and by 1 August 1941, despite 46 divisions lost in combat, the Red Army's strength was 401 divisions.^[54]

The Soviet forces were apparently unprepared despite numerous warnings from a variety of sources.^[55] They suffered much damage in the field because of mediocre officers, partial mobilization, and an incomplete reorganization.^[56] The hasty pre-war forces expansion and the over-promotion of inexperienced officers (owing to the purging of experienced officers) favored the Wehrmacht in combat.^[57] The Axis's numeric superiority rendered the combatants' divisional strength approximately equal.^[6] A generation of Soviet commanders (notably Georgy Zhukov) learned from the defeats,^[59] and Soviet victories in the Battle of Moscow, at Stalingrad, Kursk and later in Operation Bagration proved decisive.

In 1941, the Soviet government raised the bloodied Red Army's esprit de corps with propaganda stressing the defense of Motherland and nation, employing historic exemplars of Russian courage and bravery against foreign aggressors. The anti-Nazi Great Patriotic War was conflated with the Patriotic War of 1812 against Napoleon, and historical Russian military heroes, such as Alexander Nevski and Mikhail Kutuzov, appeared. Repression of the Russian Orthodox Church temporarily ceased, and priests revived the tradition of blessing arms before battle.

To encourage the initiative of Red Army commanders, the CPSU temporarily abolished political commissars, reintroduced formal military ranks and decorations, and introduced the Guards unit concept. Exceptionally heroic or high-performing units earned the Guards title (for example 1st Guards Special Rifle Corps, 6th Guards Tank Army),^[60] an elite designation denoting superior training, materiel, and pay. Punishment also was used; slackers, malingerers, those avoiding combat with self-inflicted wounds^[61] cowards, thieves, and deserters were disciplined with beatings, demotions, undesirable/dangerous duties, and summary execution by NKVD punitive detachments.

At the same time, the osobist (NKVD military counter-intelligence officers) became a key Red Army figure with the power to condemn to death and to spare the life of any soldier and (almost any) officer of the unit to which he was attached. In 1942, Stalin established the penal battalions composed of gulag inmates, Soviet PoWs, disgraced soldiers, and deserters, for hazardous front-line duty as tramplers clearing Nazi minefields, et cetera.^[62][63] Given the dangers, the maximum sentence was three months. Likewise, the Soviet treatment of Red Army personnel captured by the Wehrmacht was especially harsh. Per a 1941 Stalin directive ordered Red Army officers and soldiers were to "fight to the last" rather than surrender; Stalin stated: "There are no Soviet prisoners of war, only traitors.^[64] During and after World War II freed POWs went to special "filtration camps". Of these, by 1944, more than 90% were cleared, and about 8% were arrested or condemned to serve in penal battalions. In 1944, they were sent directly to reserve military formations to be cleared by the NKVD. Further, in 1945, about 100 filtration camps were set for repatriated POWs, and other displaced persons, which processed more than 4,000,000 people. By 1946, 80% civilians and 20% of POWs were freed, 5% of civilians, and 43% of POWs were re-drafted, 10% of civilians and 22% of POWs were sent to labor battalions, and 2% of civilians and 15% of the POWs (226,127 out of 1,539,475 total) were transferred to the Gulag.^[64][65]

During the Great Patriotic War, the Red Army conscripted 29,574,900 men in addition to the 4,826,907 in service at the beginning of the war. Of this total of 34,401,807 it lost 6,329,600 killed in action (KIA), 555,400 deaths by disease and 4,559,000 missing in action (MIA) (most captured). Of these 11,444,000, however, 939,700 rejoined the ranks in the subsequently liberated Soviet territory, and a further 1,836,000 returned from German captivity. Thus the grand total of losses amounted to 8,668,400.^[66][67] This is the official total dead, but other estimates give the number of total dead up to almost 11 million men, including 7.7 million killed or missing in action and 2.6 million POW dead (out of 5.2 million total POWs), plus 400,000 paramilitary and Soviet partisan losses.^[68] The majority of the losses, excluding POWs, were ethnic Russians (5,756,000), followed by ethnic Ukrainians (1,377,400).^[66] However, as many as 8 million of the 34 million mobilized were non-Slavic minority soldiers, and around 45 divisions formed from national minorities served from 1941 to 1943.^[69]

The German losses on the Eastern Front consisted of an estimated 3,604,800 KIA/MIA within the 1937 borders plus 900,000 ethnic Germans and Austrians outside the 1937 border (included in these numbers are men listed as missing in action or unaccounted for after the war)^[70] and 3,576,300 men reported captured (total 8,081,100); the losses of the German satellites on the Eastern Front approximated 668,163 KIA/MIA and 799,982 captured (total 1,468,145). Of these 9,549,245, the Soviets released 3,572,600 from captivity after the war, thus the grand total of the Axis losses came to an estimated 5,976,645.^[70] Regarding prisoners of war, both sides captured large numbers and had many die in captivity – one recent British^[71] figure says 3.6 of 6 million Soviet POWs died in German camps, while 300,000 of 3 million German POWs died in Soviet hands.^[72]

In 1941 the rapid progress of the initial German air and land attacks into the Soviet Union made Red Army logistical support difficult, because many depots, and most of the USSR's industrial manufacturing base, lay in the country's invaded western areas, obliging their re-establishment east of the Ural Mountains. Until then the Red Army was often required to improvise or go without weapons, vehicles, and other equipment. The 1941 decision to physically move their manufacturing capacity east of the Ural mountains kept the main Soviet support system out of German reach.^[73] In the later stages of the war, the Red Army fielded some excellent weaponry, especially artillery and tanks. The Red Army's heavy KV-1 and medium T-34 tanks outclassed most Wehrmacht armor,^[74] but in 1941 most Soviet tank units used older and inferior models.^[75]

Military administration after the October Revolution was taken over by the People's Commissariat of war and marine affairs headed by a collective committee of Vladimir Antonov-Ovseyenko, Pavel Dybenko, and Nikolai Krylenko. At the same time, Nikolay Dukhonin was acting as the Supreme Commander-in-Chief after Alexander Kerensky fled from Russia. On 12 November 1917 the Soviet government appointed Krylenko as the Supreme Commander-in-Chief, and because of an "accident" during the forceful displacement of the commander-in-chief, Dukhonin was killed on 20 November 1917. Nikolai Podvoisky was appointed as the Narkom of War Affairs, leaving Dybenko in charge of the Narkom of Marine Affairs and Ovseyenko – the expeditionary forces to the Southern Russia on 28 November 1917. The Bolsheviks also sent out their own representatives to replace front commanders of the Russian Imperial Army.

After the signing of Treaty of Brest-Litovsk on 3 March 1918, a major reshuffling took place in the Soviet military administration. On 13 March 1918 the Soviet government accepted the official resignation of Krylenko and the post of Supreme Commander-in-Chief was liquidated. On 14 March 1918 Leon Trotsky replaced Podvoisky as the Narkom of War Affairs. On 16 March 1918 Pavel Dybenko was relieved from the office of Narkom of Marine Affairs. On 8 May 1918 the All-Russian Chief Headquarters was created, headed by Nikolai Stogov and later Alexander Svechin.

On 2 September 1918 the Revolutionary Military Council (RMC) was established as the main military administration under Leon Trotsky, the Narkom of War Affairs. On 6 September 1918 alongside the chief headquarters the Field Headquarters of RMC was created, initially headed by Nikolai Rattel. On the same day the office of the Commander-in-Chief of the Armed Forces was created, and initially assigned to Jukums Vācietis (and from July 1919 to Sergey Kamenev). The Commander-in-Chief of the Armed Forces existed until April 1924, the end of Russian Civil War.

In November 1923, after the establishment of the Soviet Union, the Russian Narkom of War Affairs was transformed into the Soviet Narkom of War and Marine Affairs.

At the beginning of its existence, the Red Army functioned as a voluntary formation, without ranks or insignia. Democratic elections selected the officers. However, a decree of 29 May 1918 imposed obligatory military service for men of ages 18 to 40.^[77] To service the massive draft, the Bolsheviks formed regional military commissariats (voyennyy komissariat, abbr. voyenkomat), which as of 2006 still exist in Russia in this function and under this name. Military commissariats, however, should not be confused with the institution of military political commissars.

In the mid-1920s the territorial principle of manning the Red Army was introduced. In each region able-bodied men were called up for a limited period of active duty in territorial units, which constituted about half the army's strength, each year, for five years.^[78] The first call-up period was for three months, with one month a year thereafter. A regular cadre provided a stable nucleus. By 1925 this system provided 46 of the 77 infantry divisions and one of the eleven cavalry divisions. The remainder consisted of regular officers and enlisted personnel serving two-year terms. The territorial system was finally abolished, with all remaining formations converted to the other cadre divisions, in 1937–1938.^[79]

The Soviet military received ample funding and was innovative in its technology. An American journalist wrote in 1941:^[80]

Under Stalin's campaign for mechanization, the army formed its first mechanized unit in 1930. The 1st Mechanized Brigade consisted of a tank regiment, a motorized infantry regiment, as well as reconnaissance and artillery battalions.^[81] From this humble beginning, the Soviets would go on to create the first operational-level armored formations in history, the 11th and 45th Mechanized Corps, in 1932. These were tank-heavy formations with combat support forces included so they could survive while operating in enemy rear areas without support from a parent front.

Impressed by the German campaign of 1940 against France, the Soviet People's Commissariat of Defence (Defence Ministry, Russian abbreviation NKO) ordered the creation of nine mechanized corps on 6 July 1940. Between February and March 1941 the NKO ordered another twenty to be created. All of these formations were larger than those theorized by Tukhachevsky. Even though the Red Army's 29 mechanized corps had an authorized strength of no less than 29,899 tanks by 1941, they proved to be a paper tiger.^[82] There were actually only 17,000 tanks available at the time, meaning several of the new mechanized corps were badly under strength. The pressure placed on factories and military planners to show production numbers also led to a situation where the majority of armored vehicles were obsolescent models, critically lacking in spare parts and support equipment, and nearly three-quarters were overdue for major maintenance.^[83] By 22 June 1941 there were only 1,475 of the modern T-34s and KV series tanks available to the Red Army, and these were too dispersed along the front to provide enough mass for even local success.^[82] To illustrate this, the 3rd Mechanized Corps in Lithuania was formed up of a total of 460 tanks; 109 of these were newer KV-1s and T-34s. This corps would prove to be one of the lucky few with a substantial number of newer tanks. However, the 4th Army was composed of 520 tanks, all of which were the obsolete T-26, as opposed to the authorized strength of 1,031 newer medium tanks.^[84] This problem was universal throughout the Red Army, and would play a crucial role in the initial defeats of the Red Army in 1941 at the hands of the German armed forces.^[85]

War experience prompted changes to the way frontline forces were organised. After six months of combat against the Germans, the Stavka abolished the rifle corps which was intermediate between the army and division level because, while useful in theory, in the state of the Red Army in 1941, they proved ineffective in practice.^[86] Following the decisive victory in the Battle of Moscow in January 1942, the high command began to reintroduce rifle corps into its more experienced formations. The total number of rifle corps started at 62 on 22 June 1941, dropped to six by 1 January 1942, but then increased to 34 by February 1943, and 161 by New Year's Day 1944. Actual strengths of front-line rifle divisions, authorised to contain 11,000 men in July 1941, were mostly no more than 50% of establishment strengths during 1941,^[87] and divisions were often worn down, because of continuous operations, to hundreds of men or even less.

On the outbreak of war, the Red Army deployed mechanised corps and tank divisions whose development has been described above. The initial German attack destroyed many and, in the course of 1941, virtually all of them,(barring two in the Transbaikal Military District). The remnants were disbanded.^[88] It was much easier to coordinate smaller forces, and separate tank brigades and battalions were substituted. It was late 1942 and early 1943 before larger tank formations of corps size were fielded to employ armour in mass again. By mid-1943, these corps were being grouped together into tank armies whose strength by the end of the war could be up to 700 tanks and 50,000 men.

The Bolshevik authorities assigned to every unit of the Red Army a political commissar, or politruk, who had the authority to override unit commanders' decisions if they ran counter to the principles of the Communist Party. Although this sometimes resulted in inefficient command according to most historians, the Party leadership considered political control over the military absolutely necessary, as the army relied more and more on officers from the pre-revolutionary Imperial period and understandably feared a military coup. This system was abolished in 1925, as there were by that time enough trained Communist officers to render the counter-signing unnecessary.^[89]

The early Red Army abandoned the institution of a professional officer corps as a "heritage of tsarism" in the course of the Revolution. In particular, the Bolsheviks condemned the use of the word officer and used the word commander instead. The Red Army abandoned epaulettes and ranks, using purely functional titles such as "Division Commander", "Corps Commander" and similar titles.^[16] Insignia for these functional titles existed, consisting of triangles, squares and rhombuses (so-called "diamonds").

In 1924 (2 October) "personal" or "service" categories were introduced, from K1 (section leader, assistant squad leader, senior rifleman, etc.) to K14 (field commander, army commander, military district commander, army commissar and equivalent). Service category insignia again consisted of triangles, squares and rhombuses, but also rectangles (1 – 3, for categories from K7 to K9).

On 22 September 1935 the Red Army abandoned service categories and introduced personal ranks. These ranks, however, used a unique mix of functional titles and traditional ranks. For example, the ranks included "Lieutenant" and "Comdiv" (Комдив, Division Commander). Further complications ensued from the functional and categorical ranks for political officers (e.g., "brigade commissar", "army commissar 2nd rank"), for technical corps (e.g., "engineer 3rd rank," "division engineer"), and for administrative, medical and other non-combatant branches.

The Marshal of the Soviet Union (Маршал Советского Союза) rank was introduced on 22 September 1935. On 7 May 1940 further modifications to rationalise the system of ranks were made on the proposal by Marshal Voroshilov: the ranks of "General" and "Admiral" replaced the senior functional ranks of Combrig, Comdiv, Comcor, Comandarm in the Red Army and Flagman 1st rank etc. in the Red Navy; the other senior functional ranks ("division commissar," "division engineer," etc.) remained unaffected. The arm or service distinctions remained (e.g. general of cavalry, marshal of armoured troops).^[90] For the most part the new system restored that used by the Imperial Russian Army at the conclusion of its participation in World War I.

In early 1943 a unification of the system saw the abolition of all the remaining functional ranks. The word "officer" became officially endorsed, together with the use of epaulettes, which superseded the previous rank insignia. The ranks and insignia of 1943 did not change much until the last days of the USSR; the contemporary Russian Army uses largely the same system.

During the Civil War the commander cadres were trained at the Nicholas General Staff Academy of the Russian Empire, which became the Frunze Military Academy in the 1920s. Senior and supreme commanders were trained at the Higher Military Academic Courses, renamed the Advanced Courses for Supreme Command in 1925. The 1931 establishment of an Operations Faculty at the Frunze Military Academy supplemented these courses. The General staff Academy was reinstated on 2 April 1936, and became the principal military school for the senior and supreme commanders of the Red Army.^[91]

The late 1930s saw purges of the Red Army leadership which occurred concurrently with Stalin's Great Purge of Soviet society. In 1936 and 1937, at the orders of Stalin, thousands of Red Army senior officers were dismissed from their commands. The purges had the objective of cleansing the Red Army of the "politically unreliable elements," mainly among higher-ranking officers. This inevitably provided a convenient pretext for the settling of personal vendettas or to eliminate competition by officers seeking the same command. Many army, corps, and divisional commanders were sacked: most were imprisoned or sent to labor camps; others were executed. Among the victims was the Red Army's primary military theorist, Marshal Mikhail Tukhachevsky, who was perceived by Stalin as a potential political rival.^[92] Officers who remained soon found all of their decisions being closely examined by political officers, even in mundane matters such as record-keeping and field training exercises.^[93] An atmosphere of fear and unwillingness to take the initiative soon pervaded the Red Army; suicide rates among junior officers rose to record levels.^[93] The purges significantly impaired the combat capabilities of the Red Army. Hoyt concludes "the Soviet defense system was damaged to the point of incompetence" and stresses "the fear in which high officers lived."^[94] Clark says, "Stalin not only cut the heart out of the army, he also gave it brain damage."^[95] Lewin identifies three serious results: the loss of experienced and well-trained senior officers; the distrust it caused among potential allies especially France; and the encouragement it gave Germany.^[96][97]

Recently declassified data indicate that in 1937, at the height of the Purges, the Red Army had 114,300 officers, of whom 11,034 were dismissed. In 1938, the Red Army had 179,000 officers, 56% more than in 1937, of whom a further 6,742 were dismissed. In the highest echelons of the Red Army the Purges removed 3 of 5 marshals, 13 of 15 army generals, 8 of 9 admirals, 50 of 57 army corps generals, 154 out of 186 division generals, all 16 army commissars, and 25 of 28 army corps commissars.^[98]

The result was that the Red Army officer corps in 1941 had many inexperienced senior officers. While 60% of regimental commanders had two years or more of command experience in June 1941, and almost 80% of rifle division commanders, only 20% of corps commanders, and 5% or fewer army and military district commanders, had the same level of experience. ^[99]

The significant growth of the Red Army during the high point of the purges may have worsened matters. In 1937, the Red Army numbered around 1.3 million, increasing to almost three times that number by June 1941. The rapid growth of the army necessitated in turn the rapid promotion of officers regardless of experience or training.^[93] Junior officers were appointed to fill the ranks of the senior leadership, many of whom lacked broad experience.^[93] This action in turn resulted in many openings at the lower level of the officer corps, which were filled by new graduates from the service academies. In 1937, the entire junior class of one academy was graduated a year early to fill vacancies in the Red Army.^[93] Hamstrung by inexperience and fear of reprisals, many of these new officers failed to impress the large numbers of incoming draftees to the ranks; complaints of insubordination rose to the top of offenses punished in 1941,^[93] and may have exacerbated instances of Red Army soldiers deserting their units during the initial phases of the German offensive of that year.^[93]

By 1940, Stalin began to relent, restoring approximately one-third of previously dismissed officers to duty.^[93] However, the effect of the purges would soon manifest itself in the Winter War of 1940, where Red Army forces generally performed poorly against the much smaller Finnish Army, and later during the German invasion of 1941, in which the Germans were able to rout the Soviet defenders partially due to inexperience amongst the Soviet officers.^[100]

In Lithuania, Red Army personnel robbed local shops.^[101] Following the fall of East Prussia, Soviet soldiers carried out large-scale rapes in Germany, especially noted in Berlin until the beginning of May 1945.^[102][103]They were often committed by rear echelon units.^[104]

The Soviet Union expanded its indigenous arms industry as part of Stalin's industrialisation program in the 1920s and 1930s.