Battles of Khalkhin Gol The Battles of Khalkhyn Gol ( ; ; ) constituted the decisive engagement of the undeclared Soviet – Japanese border conflicts fought among the Soviet Union , Mongolia and the Empire of Japan in 1939 . The conflict was named after the river Khalkhyn Gol , which passes through the battlefield . In Japan , the decisive battle of the conflict is known as the after a nearby village on the border between Mongolia and Manchuria . The battles resulted in the defeat of the Japanese Sixth Army . Background . After the occupation of Manchuria in 1931 , Japan turned its military interests to Soviet territories that bordered those areas . The first major Soviet - Japanese border incident , the Battle of Lake Khasan , happened in 1938 in Primorye . Clashes between Japanese and Soviet forces frequently occurred on the border of Manchuria . In 1939 , Manchuria was a puppet state of Japan , known as Manchukuo and Mongolia was a communist state allied with the Soviet Union , known as the Mongolian People ' s Republic . The Japanese maintained that the border between Manchukuo and Mongolia was the Khalkhyn Gol ( English " Khalkha River " ) which flows into Lake Buir . In contrast , the Mongolians and their Soviet allies maintained that the border ran some east of the river , just east of Nomonhan village . The principal occupying army of Manchukuo was the Kwantung Army of Japan , consisting of some of the best Japanese units in 1939 . However , the western region of Manchukuo was garrisoned by the newly formed IJA 23d Infantry Division at Hailar , under General Michitarō Komatsubara and included several Manchukuoan army and border guard units . The Soviet forces consisted of the 57th Special Corps , forward deployed from the Trans - Baikal Military District , responsible for defending the border between Siberia and Manchuria . The Mongolian troops mainly consisted of cavalry brigades and light artillery units , and proved to be effective and agile , but lacked armour and manpower in sufficient numbers . In 1939 , the Japanese Cabinet sent instructions to the Kwantung Army to strengthen and fortify Manchukuo ' s borders with Mongolia and the Soviet Union . Additionally , the Kwantung Army , which had long been stationed in Manchuria far from the Japanese home islands , had become largely autonomous and tended to act without approval from , or even against the direction of , the Japanese government . May , June , and July actions . The incident began on 11 May 1939 . A Mongolian cavalry unit of some 70 – 90 men had entered the disputed area in search of grazing for their horses . On that day , Manchukuoan cavalry attacked the Mongolians and drove them back across the Khalkhin Gol . On 13 May , the Mongolian force returned in greater numbers and the Manchukoans were unable to dislodge them . On 14 May , Lt . Col . Yaozo Azuma led the reconnaissance regiment of 23rd Infantry Division , supported by the 64th Infantry Regiment of the same division , under Colonel Takemitsu Yamagata , into the territory and the Mongolians withdrew . Soviet and Mongolian troops returned to the disputed region , however , and Azuma ' s force again moved to evict them . This time things turned out differently , as the Soviet - Mongolian forces surrounded Azuma ' s force on 28 May and destroyed it . The Azuma force suffered eight officers and 97 men killed and one officer and 33 men wounded , for 63 % total casualties . The commander of the Soviet forces and the Far East Front was Comandarm Grigori Shtern from May 1938 . Both sides began building up their forces in the area : soon Japan had 30 , 000 men in the theater . The Soviets dispatched a new Corps commander , Comcor Georgy Zhukov , who arrived on 5 June and brought more motorized and armored forces ( I Army Group ) to the combat zone . Accompanying Zhukov was Comcor Yakov Smushkevich with his aviation unit . J . Lkhagvasuren , Corps Commissar of the Mongolian People ' s Revolutionary Army , was appointed Zhukov ' s deputy . On 27 June , IJAF ' s 2nd Air Brigade ( 2nd AB ) struck the Soviet air base at Tamsak - Bulak in Mongolia . The Japanese won this engagement , but the strike had been ordered by the Kwangtung Army without getting permission from Imperial Japanese Army headquarters in Tokyo . In an effort to prevent the incident from escalating , Tokyo promptly ordered the Japanese Army Air Force to not conduct any more air strikes against Soviet airbases . Throughout June , there were continuing reports of Soviet and Mongolian activity on both sides of the river near Nomonhan , and small - scale attacks on isolated Manchukoan units . At the end of the month , the commander of the Japanese 23rd Infantry Division , Lt . Gen . Michitarō Komatsubara , was given permission to " expel the invaders " . The Japanese plan was for a two - pronged assault . Three regiments plus part of a fourth , including three from the 23rd Division — the 71st and the 72nd Infantry Regiment s , plus a battalion of the 64th Infantry Regiment — and the 26th Infantry Regiment under Colonel Shinichiro Sumi , borrowed from the 7th Infantry Division , would advance across the Khalkin Gol , destroy Soviet forces on Baintsagan Hill on the west bank , then make a left turn and advance south to the Kawatama Bridge . The second prong of the attack would be the task of the IJA 1st Tank Corps ( 1st TC ) ( Yasuoka Detachment ) , consisting of the 3rd and 4th Tank Regiment s , plus a part of the 64th Infantry Regiment , a battalion from the 28th Infantry Regiment , detached from the 7th Infantry , 24th Engineer Regiment , and a battalion from the 13th Field Artillery Regiment , all under the overall command of Lieutenant General Yasuoka Masaomi . This force would attack Soviet troops on the east bank of the Khalkhyn Gol and north of the Holsten River . The two Japanese thrusts were intending to join together on the wings . The northern task force succeeded in crossing the Khalkhyn Gol , driving the Soviets from Baintsagan Hill , and advancing south along the west bank . However , Zhukov , perceiving the threat , launched a counterattack with 450 tanks and armored cars . The Soviet armored force , despite being unsupported by infantry , attacked the Japanese on three sides and nearly encircled them . The Japanese force , further handicapped by having only one pontoon bridge across the river for supplies , was forced to withdraw , recrossing the river on 5 July . Meanwhile , the " 1st Tank Corps " of the Yasuoka Detachment ( the southern task force ) attacked on the night of 2 July , moving in the darkness to avoid the Soviet artillery on the high ground of the river ' s west bank . A pitched battle ensued in which the Yasuoka Detachment lost over half its armor , and could not break through the Soviet forces on the east bank and reach the Kawatama Bridge . After a Soviet counterattack on 9 July threw the battered , depleted Yasuoka Detachment back , it was dissolved and Yasuoka was relieved . The two armies continued to spar with each other over the next two weeks along a front running along the east bank of the Khalkhyn Gol to its junction with the Holsten River . Zhukov , whose army was away from its base of supply , assembled a fleet of 2600 trucks to supply his troops , while the Japanese suffered severe supply problems due to a lack of similar motor transport . On 23 July , the Japanese launched another large - scale assault , sending the 64th and 72nd Infantry Regiments against Soviet forces defending the Kawatama Bridge . Japanese artillery supported the attack with a massive barrage that consumed more than half of their ammunition stores over a period of two days . The attack made some progress but failed to break through Soviet lines and reach the bridge . The Japanese disengaged from the attack on 25 July due to mounting casualties and depleted artillery stores . They had suffered over five thousand casualties to this point but still had 75 , 000 men and some hundred planes facing the Soviet forces . The battle drifted into a stalemate . August : Zhukov ' s strike . The Japanese regrouped and planned a third major offensive against the Soviets for 24 August . However , with war apparently imminent in Europe , Zhukov planned a major offensive on 20 August , to clear the Japanese from the Khalkhin Gol region and end the fighting . Zhukov assembled a powerful armored force of three tank brigades ( the 4th , 6th and 11th ) , and two mechanized brigades ( the 7th and 8th , which were armored car units with attached infantry support ) . This force was allocated to the Soviet left and right wings . The entire Soviet force consisted of three rifle divisions , two tank divisions and two more tank brigades ( in all , some 498 BT - 5 and BT - 7 tanks ) , two motorized infantry divisions , and over 550 fighters and bombers . The Mongolians committed two cavalry divisions . By contrast , at the point of contact , the Kwantung Army had only Lieutenant General Michitarō Komatsubara ' s 23rd Infantry Division , which with various attached forces was equivalent to two light infantry divisions . Its headquarters had been at Hailar , over from the fighting . Japanese intelligence had also failed to detect the scale of the Soviet buildup or the scope of the imminent offensive . Zhukov decided it was time to break the stalemate . At 05 : 45 on 20 August 1939 , Soviet artillery and 557 fighters and bombers attacked Japanese positions , the first fighter – bomber offensive in Soviet Air Force history . Approximately 50 , 000 Soviet and Mongolian soldiers of the 57th Special Corps defended the east bank of the Khalkhyn Gol . Three infantry divisions and a tank brigade crossed the river , supported by massed artillery and the Soviet Air Force . Once the Japanese were pinned down by the attack of Soviet center units , Soviet armored units swept around the flanks and attacked the Japanese in the rear , achieving a classic double envelopment . When the Soviet wings linked up at Nomonhan village on 25 August , the Japanese 23rd Infantry Division was trapped . On 26 August , a Japanese counterattack to relieve the 23rd Division failed . On 27 August , the 23rd Division attempted to break out of the encirclement , but also failed . When the surrounded forces refused to surrender , they were again hit with artillery and air attacks . By 31 August , Japanese forces on the Soviet side of the border were destroyed , leaving remnants of the 23rd Division on the Manchurian side . The Soviets had achieved their objective . Komatsubara refused to accept the outcome and prepared a counteroffensive . This was canceled when a cease - fire was signed in Moscow . While Zhukov defeated the Japanese forces from Soviet territory , Joseph Stalin had made a deal with Nazi Germany . After the Soviet success at Nomonhan , Stalin decided to proceed with the Molotov - Ribbentrop Pact , which was announced on 24 August . With no further threat of a " second front " from Japan , Stalin was free to concentrate on war in Europe and the Soviet Union and Japan agreed to a cease - fire on 15 September , which took effect the following day . Free from a threat in the Far East , Stalin proceeded with the Soviet invasion of Poland on 17 September . Aftermath . Casualty estimates vary widely : The Japanese officially reported 8 , 440 killed and 8 , 766 wounded , while the Soviets initially claimed 9 , 284 total casualties . Some sources , however , put the Japanese casualties at 45 , 000 or more soldiers killed , with Soviet casualties of at least 17 , 000 . It is likely figures published at the time were reduced for propaganda purposes . In recent years , with the opening of the Soviet archives , a more accurate assessment of Soviet casualties has emerged from the work of Grigoriy Krivosheev , citing 7 , 974 killed and 15 , 251 wounded . In the newer , 2001 edition , the Soviet losses are given as 9703 killed and missing ( 6472 killed and died of wounds during evacuation , 1152 died of wounds in hospitals , 8 died of disease , 2028 missing , 43 non - combat dead ) , the number of wounded is unchanged ; there were a further 2225 hospitalizations due to sickness . Similar research into Japanese casualties has yet to take place . Nomonhan was the first use of airpower on a massive scale in a high intensity battle to obtain a specific military objective . Aircraft ordnance expenditures at Nomonhan . USSR ( Russia ) : Bomber sorties 2 , 015 , Fighter sorties 18 , 509 ; 7 . 62mm machine gun rounds fired 1 , 065 , 323 ; 20mm cannon rounds expended 57 , 979 ; bombs dropped 78 , 360 ( 1200 tons ) . Japan : Fighter / bomber sorties 10 , 000 ( estimated ) ; 7 . 7mm machine gun rounds fired 1 , 600 , 000 ; bombs dropped 970 tons . Aircraft losses summary and notes . Combat losses include aircraft shot down during aerial combat , written off due to combat damage or destroyed on the ground . Non - combat losses include aircraft that were lost due to accidents , as well as write - offs of warplanes due to the end of their service life . Thus Soviet combat losses amount to 163 fighters , 44 bombers and a reconnaissance aircraft , with further 385 fighters and 51 bombers requiring repairs due to combat damage . VVS personnel were losses were 88 killed in aerial combat , 11 killed by anti - aircraft artillery , 65 missing , 6 killed in airstrikes and 4 dead of wounds ( 174 total ) and 113 wounded . The Japanese combat losses were 97 fighters , 25 bombers and 41 other ( mostly reconnaissance ) , while 128 fighters , 54 bombers and 38 other required repairs due to combat damage . The Japanese airforce suffered 152 dead and 66 seriously wounded . Summary . While this engagement is little - known in the West , it played an important part in subsequent Japanese conduct in World War II . This defeat , together with other factors , moved the Imperial General Staff in Tokyo away from the policy of the North Strike Group favored by the Army , which wanted to seize Siberia as far as Lake Baikal for its resources . ( See illustration . ) Other factors included the signing of the Nazi - Soviet non - aggression pact , which deprived the Army of the basis of its war policy against the USSR . Nomonhan earned the Kwantung Army the displeasure of officials in Tokyo , not so much due to its defeat , but because it was initiated and escalated without direct authorization from the Japanese government . Politically , the defeat also shifted support to the South Strike Group , favored by the Navy , which wanted to seize the resources of Southeast Asia , especially the petroleum and mineral - rich Dutch East Indies . Two days after the Eastern Front of World War II broke out , the Japanese army and navy leaders adopted on 24 June 1941 a resolution " not intervening in German Soviet war for the time being " . In August 1941 , Japan and the Soviet Union reaffirmed their neutrality pact . Since the European colonial powers were weakening and suffering early defeats in the war with Germany , coupled with their embargoes on Japan ( especially of vital oil ) in the second half of 1941 , Japan ' s focus was ultimately focused on the south , and led to its decision to launch the attack on Pearl Harbor , on 7 December that year . Despite plans being carried out for a potential war against the USSR ( particularly contingent on German advances towards Moscow ) , the Japanese would never launch an offensive against the Soviet Union . In 1941 , the two countries signed agreements respecting the borders of Mongolia and Manchukuo and pledging neutrality towards each other . In the closing months of World War II , the Soviet Union would break the Neutrality Pact by invading the Japanese territories in Manchuria , Korea , and the southern part of Sakhalin island . The battle was the first victory for the soon - to - be - famous Soviet general Georgy Zhukov , earning him the first of his four " Hero of the Soviet Union " awards . The other generals , Grigoriy Shtern and Yakov Smushkevich , whose roles were no less important and who also earned the Hero , would instead be executed in the 1941 Purges . Zhukov himself was promoted and transferred west to the Kiev district . The battle experience gained by Zhukov was put to good use in December 1941 at the Battle of Moscow . Zhukov was able to use this experience to launch the first successful Soviet counteroffensive against the German invasion of 1941 . Many units of the Siberian and other trans - Ural armies were part of this attack , and the decision to move the divisions from Siberia was aided by the Soviet spy Richard Sorge in Tokyo , who was able to alert the Soviet government that the Japanese were looking south and were unlikely to launch another attack against Siberia in the immediate future . A year after defending Moscow against the advancing Germans , Zhukov planned and executed the Red Army ' s offensive at the Battle of Stalingrad , using a technique very similar to Khalkhin Gol , in which the Soviet forces held the enemy fixed in the center , built up a mass of force in the area undetected , and launched a pincer attack on the wings to trap the enemy army . A GRU colonel , Vasiliy Novobranets ( Василий Новобранец ) stated that Zhukov revised the original battle report to conceal huge losses suffered by his forces , and that the battle result was not as much decided by tactics , but purely due to the numerical superiority in troops , supplies , and equipment . The Japanese researchers similarly considered the result not a failing of tactics , but one that simply highlighted a need to address the material disparity between itself and its neighbors . . After the war , at the International Military Tribunal for the Far East , fourteen Japanese were charged by delegates of conquering Soviet Union , with having " initiated a war of aggression . . . against the Mongolian People ' s Republic in the area of the Khalkhin - Gol River " and also with having waged a war " in violation of international law " against the USSR . Kenji Doihara , Hiranuma Kiichirō , and Seishirō Itagaki were convicted on these charges . The Mongolian town of Choibalsan , in the Dornod Province where the battle was fought , is the location of the " G . K . Zhukov Museum " , dedicated to Zhukov and the 1939 battle . Ulaanbaatar , Mongolia also has a " G . K . Zhukov Museum " with information about the battle . In popular culture . The Battles of Khalkhin Gol were depicted in the 2011 South Korean war film " My Way " . The film was inspired by the true tale of a Korean named Yang Kyoungjong who was captured by the Americans on D - Day . Yang Kyoungjong was conscripted in the Japanese Imperial Army , fought in the Battles of Khalkhin Gol against the Red Army , then was enlisted to the Red Army , fought against the Germans and after being taken prisoner he joined the Wehrmacht .