Soviet–Japanese War

At the Tehran Conference in November 1943, Joseph Stalin agreed that the Soviet Union would enter the war against Japan once Germany was defeated. At the Yalta Conference in February 1945, Stalin agreed to Allied pleas to enter World War II in the Pacific Theater within three months of the end of the war in Europe. On July 26, the US, the UK, and China made the Potsdam Declaration, an ultimatum calling for the Japanese surrender that if ignored would lead to their "prompt and utter destruction".

The commencement of the invasion fell between the US atomic bombings of Hiroshima on August 6 and Nagasaki on August 9. Although Stalin had been told virtually nothing of the US and UK's atomic bomb program by Allied governments, the date of the invasion was foreshadowed by the Yalta agreement, the date of the German surrender, and the fact that, on August 3, Marshal Vasilevsky reported to Stalin that, if necessary, he could attack on the morning of August 5. The timing was well-planned and enabled the Soviet Union to enter the Pacific Theater on the side of the Allies, as previously agreed, before the war's end.[17] The invasion of the second largest Japanese island of Hokkaido, originally planned by the Soviets to be part of the territory taken,[18] was held off due to apprehension of the US' new position as an atomic power.[19][20][21][22]

At 11 pm Trans-Baikal time on August 8, 1945, Soviet foreign minister Vyacheslav Molotov informed Japanese ambassador Naotake Satō that the Soviet Union had declared war on Japan, and that from August 9 the Soviet Government would consider itself to be at war with Japan.[23] At one minute past midnight Trans-Baikal time on August 9, 1945, the Soviets commenced their invasion simultaneously on three fronts to the east, west and north of Manchuria. The operation was subdivided into smaller operational and tactical parts:

• Khingan–Mukden Offensive Operation (August 9, 1945 – September 2, 1945)
• Harbin–Kirin Offensive Operation (August 9, 1945 – September 2, 1945)
• Sungari Offensive Operation (August 9, 1945 – September 2, 1945)

and subsequently

• South Sakhalin Operation (August 11, 1945 – August 25, 1945)
  • Soviet assault on Maoka (August 19, 1945 - August 22, 1945)
• Seishin Landing Operation (August 13, 1945 – August 16, 1945)
• Kuril Landing Operation (August 18, 1945 – September 1, 1945)

Though the battle extended beyond the borders traditionally known as Manchuria – that is, the traditional lands of the Manchus – the coordinated and integrated invasions of Japan's northern territories has also been called the Battle of Manchuria.[24] Since 1983, the operation has sometimes been called Operation August Storm, after American Army historian Lieutenant-Colonel David Glantz used this title for a paper on the subject.[1] It has also been referred to by its Soviet name, the Manchurian Strategic Offensive Operation, but this name refers more to the Soviet invasion of Manchuria than to the whole war.

This offensive should not be confused with the Soviet–Japanese Border Wars (particularly the Battle of Khalkhin Gol/Nomonhan Incident of May–September 1939), that ended in Japan's defeat in 1939, and led to the Soviet–Japanese Neutrality Pact.[25]

The Russo-Japanese War of the early 20th century resulted in a Japanese victory and the Treaty of Portsmouth by which, in conjunction with other later events including the Mukden Incident and Japanese invasion of Manchuria in September 1931, Japan eventually gained control of Korea, Manchuria and South Sakhalin. In the late 1930s were a number of Soviet-Japanese border incidents, the most significant being the Battle of Lake Khasan (Changkufeng Incident, July–August 1938) and the Battle of Khalkhin Gol (Nomonhan Incident, May–September 1939), which led to the Soviet–Japanese Neutrality Pact[25][26] of April 1941. The Neutrality Pact freed up forces from the border incidents and enabled the Soviets to concentrate on their war with Germany and the Japanese to concentrate on their southern expansion into Asia and the Pacific Ocean.

With success at the Battle of Stalingrad and the eventual defeat of Germany becoming increasingly certain, the Soviet attitude to Japan changed, both publicly, with Stalin making speeches denouncing Japan, and privately, with the Soviets building up forces and supplies in the Far East. At the Tehran Conference (November 1943), Stalin, Winston Churchill, and Franklin Roosevelt agreed that the Soviet Union would enter the war against Japan once Germany was defeated. Stalin faced a dilemma since he wanted to avoid a two-front war at almost any cost but also wanted to extract gains in the Far East as well as Europe. The only way that Stalin could make Far Eastern gains without a two-front war would be for Germany to surrender before Japan.

The Soviet–Japanese Neutrality Pact caused the Soviets to make it policy to intern Allied aircrews who landed in Soviet territory after operations against Japan, but airmen held in the Soviet Union under such circumstances were usually allowed to "escape" after some period of time.[27] Nevertheless, even before the defeat of Germany, the Soviet buildup in the Far East had steadily accelerated. By early 1945, it had become apparent to the Japanese that the Soviets were preparing to invade Manchuria, but they were unlikely to attack prior to Germany's defeat. In addition to their problems in the Pacific, the Japanese realised that they needed to determine when and where a Soviet invasion would occur.

At the Yalta Conference (February 1945), Stalin secured from Roosevelt the promise of Stalin's Far Eastern territorial desires in return for agreeing to enter the Pacific War within two or three months of the defeat of Germany. By mid-March 1945, things were not going well in the Pacific for the Japanese, who withdrew their elite troops from Manchuria to support actions in the Pacific. Meanwhile, the Soviets continued their Far Eastern buildup. The Soviets had decided that they did not wish to renew the Neutrality Pact. The Neutrality Pact required that twelve months before its expiry, the Soviets must advise the Japanese and so on April 5, 1945, they informed the Japanese that they did not wish to renew the treaty.[28] That caused the Japanese considerable concern,[29][30] but the Soviets went to great efforts to assure the Japanese that the treaty would still be in force for another twelve months and that the Japanese had nothing to worry about.[31]

On May 9, 1945 (Moscow Time), Germany surrendered and so if the Soviets were to honour the Yalta Agreement, they would need to enter war with Japan by August 9, 1945. The situation continued to deteriorate for the Japanese, now the only Axis power left in the war. They were keen to remain at peace with the Soviets and extend the Neutrality Pact[31] and also wanted to achieve an end to the war. Since Yalta, they had repeatedly approached or tried to approach the Soviets to extend the Neutrality Pact and to enlist the Soviets in negotiating peace with the Allies. The Soviets did nothing to discourage the Japanese hopes and drew the process out as long as possible but continued to prepare their invasion forces.[31] One of the roles of the Cabinet of Admiral Baron Suzuki, which took office in April 1945, was to try to secure any peace terms short of unconditional surrender.[32] In late June, they approached the Soviets (the Neutrality Pact was still in place), inviting them to negotiate peace with the Allies in support of Japan, providing them with specific proposals and in return, they offered the Soviets very attractive territorial concessions. Stalin expressed interest, and the Japanese awaited the Soviet response. The Soviets continued to avoid providing a response. The Potsdam Conference was held from July 16 to August 2, 1945. On July 24, the Soviet Union recalled all embassy staff and families from Japan. On July 26, the conference produced the Potsdam Declaration whereby Churchill, Harry S. Truman and Chiang Kai-shek (the Soviet Union was not officially at war with Japan) demanded the unconditional surrender of Japan. The Japanese continued to wait for the Soviet response and avoided responding to the declaration.[31]

The Japanese had been monitoring Trans-Siberian Railway traffic and Soviet activity to the east of Manchuria and the Soviet delaying tactics, which suggested to them that the Soviets would not be ready to invade east Manchuria before the end of August. They did not have any real idea and no confirming evidence as to when or where any invasion would occur.[12] They had estimated that an attack was not likely in August 1945 or before spring 1946, but Stavka had planned for a mid-August 1945 offensive and had concealed the buildup of a force of 90 divisions. Many had crossed Siberia in their vehicles to avoid straining the rail link.[33]

The Japanese were caught completely by surprise when the Soviets declared war an hour before midnight on 8 August 1945 and invaded simultaneously on three fronts just after midnight on 9 August.

The operation was carried out as a classic double pincer movement over an area the size of Western Europe. In the western pincer, the Red Army advanced over the deserts and mountains from Mongolia, far from their resupply railways. That confounded the Japanese military analysis of Soviet logistics, and the defenders were caught by surprise in unfortified positions. The Kwantung Army commanders, involved in a planning exercise at the time of the invasion, were away from their forces for the first 18 hours of conflict. Communication infrastructure was poor, and communication was lost with forward units very early. The Kwantung Army had a formidable reputation as fierce and relentless fighters, and even though weak and unprepared, they put up strong resistance in the town of Hailar, which tied down some of the Soviet forces. At the same time, Soviet airborne units were used to seize airfields and city centers in advance of the land forces and to ferry fuel to the units that had outrun their supply lines. The Soviet pincer from the east crossed the Ussuri and advanced around Khanka Lake and attacked towards Suifenhe. Although Japanese defenders fought hard and provided strong resistance, the Soviets proved to be overwhelming.

After a week of fighting during which Soviet forces had penetrated deep into Manchukuo, Japanese Emperor Hirohito recorded the Gyokuon-hōsō, which was broadcast on radio to the Japanese nation on August 15, 1945. The idea of surrender was incomprehensible to the Japanese people, and combined with Hirohito's use of formal and archaic language, the fact that he did not use the word "surrender", the poor quality of the broadcast, and the poor lines of communication, there was some confusion for the Japanese about what the announcement meant. The Imperial Japanese Army Headquarters did not immediately communicate the ceasefire order to the Kwantung Army, and many elements of the Army either did not understand it or ignored it. Hence, pockets of fierce resistance from the Kwantung Army continued, and the Soviets continued their advance, largely avoiding the pockets of resistance, reaching Mukden, Changchun and Qiqihar by August 20. On the Soviet right flank, the Soviet-Mongolian Cavalry-Mechanized Group had entered Inner Mongolia and quickly took Dolon Nur and Kalgan. The Emperor of Manchukuo and former Emperor of China, Puyi, was captured by the Soviet Red Army. The ceasefire order was eventually communicated to the Kwantung Army but not before the Soviet Union had made most of their territorial gains.

On August 18, several Soviet amphibious landings had been conducted ahead of the land advance: three in northern Korea, one in South Sakhalin, and one in the Chishima Islands. In Korea at least, there were already Soviet soldiers waiting for the troops coming overland. In Karafuto and the Chishimas, that meant a sudden and undeniable establishment of Soviet sovereignty.

On August 10, the US government proposed to the Soviet government to divide the occupation of Korea between them at the 38th parallel north. The Americans were surprised that the Soviet government accepted. Soviet troops were able to move freely by rail, and there was nothing to stop them from occupying the whole of Korea.[34] Soviet forces began amphibious landings in northern Korea by August 14 and rapidly took over the northeast of the peninsula, and on August 16, they landed at Wonsan.[35] On August 24, the Red Army entered Pyongyang and established a military government over Korea north of the 38th parallel. American forces landed at Incheon on September 8 and took control of the south.[36][37]

About 1,831,000 Soviet personnel have been awarded the Medal "For the Victory over Japan" since 30 September 1945.

Since the first major Japanese military defeats in the Pacific in the summer of 1942, the civilian leaders of Japan had come to realise that the Japanese military campaign was economically unsustainable, as Japan did not have the industrial capacity to fight the United States, China and the British Empire at the same time, and there were a number of initiatives to negotiate a cessation of hostilities and the consolidation of Japanese territorial and economic gains. Hence, elements of the non-military leadership had first made the decision to surrender as early as 1943. The major issue was the terms and conditions of surrender, not the issue of surrender itself. For a variety of diverse reasons, none of the initiatives was successful, the two major reasons being the Soviet Union's deception and delaying tactics and the attitudes of the "Big Six", the powerful Japanese military leaders.[13]

The Manchurian Strategic Offensive Operation, along with the atomic bombings of Hiroshima and Nagasaki, combined to break the Japanese political deadlock and force the Japanese leaders to accept the terms of surrender demanded by the Allies.

In the "Sixty Years after Hiroshima" issue of The Weekly Standard, the American historian Richard B. Frank points out that there are a number of schools of thought with varying opinions of what caused the Japanese to surrender. He describes what he calls the "traditionalist" view, which asserts that the Japanese surrendered because the Americans dropped the atomic bombs. He goes on summarize other points of view in conflict with the traditionalist view: namely, that the Japanese government saw their situation as hopeless and was already ready to surrender before the atomic bombs and Soviet war.[38]

Tsuyoshi Hasegawa's research has led him to conclude that the atomic bombings were not the principal reason for Japan's capitulation. He argues that Japan's leaders were impacted more by the swift and devastating Soviet victories on the mainland in the week after Joseph Stalin's August 8 declaration of war because the Japanese strategy to protect the home islands was designed to fend off an Allied invasion from the south and left virtually no spare troops to counter a Soviet threat from the north. Furthermore, the Japanese could no longer hope to achieve a negotiated peace with the Allies by using the Soviet Union as a mediator with the Soviet declaration of war. That, according to Hasegawa, amounted to a "strategic bankruptcy" for the Japanese and forced their message of surrender on August 15, 1945.[39][16] Others with similar views include the Battlefield series documentary,[2][11] among others, but all, including Hasegawa, state that the surrender was not caused by only one factor or event.

The Soviet invasion and occupation of the defunct Manchukuo marked the start of a traumatic period for the more than one million residents of the puppet state who were of Japanese descent. The situation for the Japanese military occupants was clear, but the Japanese colonists who had made Manchukuo their home, particularly those born in Manchukuo, were now stateless and homeless, and the (non-Japanese) Manchurians wanted to be rid of these foreigners. Many residents were killed, and others ended up in Siberian prisons for up to 20 years. Some made their way to the Japanese home islands, where they were also treated as foreigners.[32][40][41][42]

Manchuria was "cleansed" by Soviet forces of any potential military resistance. With Soviet support for the spread of communism,[43] Manchuria provided the main base of operations for Mao Zedong's forces, who proved victorious in the following four years of the Chinese Civil War. The military successes in Manchuria and China by the Communist Chinese led to the Soviet Union giving up their rights to bases in China, promised by the Western Allies, because all of the land deemed by the Soviets to be Chinese, as distinct from what the Soviets considered to be Soviet land that had been occupied by the Japanese, was eventually turned over to the People's Republic of China.[43] Before leaving Manchuria, Soviet forces and bureaucracy dismantled almost all of the portable parts of the considerable Japanese-built industry in Manchuria and relocated it to "restore industry in war-torn Soviet territory." What was not portable was either disabled or destroyed since the Soviets had no desire for Manchuria to be an economic rival, particularly to the underdeveloped Far Eastern Soviet Territories.[32] After the establishment of the People's Republic of China, the bulk of the Soviet economic assistance went to Manchuria to help rebuilding the region's industry.[44]

As agreed at Yalta, the Soviet Union had intervened in the war with Japan within three months of the German surrender and so was therefore entitled to annex the territories of South Sakhalin and the Kuril Islands and also to preeminent interests over Port Arthur and Dalian, with its strategic rail connections, via the China Changchun Railway, a company owned jointly by China and the Soviet Union that operated all railways of the former Manchukuo. The territories on the Asian mainland were transferred to the full control of the People's Republic of China in 1955. The other possessions are still administered by the Soviet Union's successor state, Russia. The annexation of South Sakhalin and the Kuril Islands is of great importance as the Sea of Okhotsk became a Soviet inland sea, which continues to have great strategic benefit to Russia.

The division of Korea between the Soviet and US occupations led to the creation of the separate states of North and South Korea, a precursor to the Korean War five years later.[45]

• Battles of Khalkhin Gol
• Battle of Mutanchiang
• Battle of Shumshu
• Military history of Japan
• Military history of the Soviet Union
• Kuril Islands dispute
• Project Hula

• Despres, J, Dzirkals, L, et al. (1976). Timely Lessons of History : The Manchurian Model for Soviet Strategy. Santa Monica, RAND: 103. (available on-line)
• Duara, P. (2006). The New Imperialism and the Post-Colonial Developmental State: Manchukuo in comparative perspective. Japan Focus.
• Garthoff, R L. (1966). Soviet Military Policy : A Historical Analysis. London, Faber and Faber.
• Garthoff, R L. (1969). The Soviet Manchurian Campaign, August 1945. Military Affairs XXXIII(Oct 1969): 312–336.
• Glantz, David M. (1983a). August Storm: The Soviet 1945 Strategic Offensive in Manchuria, Leavenworth Paper No.7, Command and General Staff College, Fort Leavenworth, Kansas, February 1983.
• Glantz, David M. (1983b). August Storm: Soviet Tactical and Operational Combat in Manchuria, 1945, Leavenworth Paper No.8, Command and General Staff College, Fort Leavenworth, Kansas, June 1983.
• Glantz, David M. (1995) The Soviet Invasion of Japan. Quarterly Journal of Military History, vol. 7, no. 3, Spring 1995.
• Glantz, David M. (2003). The Soviet Strategic Offensive in Manchuria, 1945 (Cass Series on Soviet (Russian) Military Experience, 7). Routledge. ISBN 0-7146-5279-2.
• Gordin, Michael D. (2005). Five Days in August: How World War II Became a Nuclear War. (Extracts on-line)
• Hallman, A L. (1995). Battlefield Operational Functions and the Soviet Campaign against Japan in 1945. Quantico, Virginia, United States Marine Corps Command and Staff College. (available on-line)
• Hasegawa, T. (Ed.) (2007). The End of the Pacific War. (Extracts on-line)
• Ishiwatari, H, Mizumachi, K, et al. (1946) No.77 – Japanese Preparations for Operations in Manchuria (prior to 1943). Tokyo, Military History Section, Headquarters, Army Forces Far East, US Army.
• Jowett, Phillip (2005). Rays of the Rising Sun: Japan's Asian Allies 1931–45 Volume 1: China and Manchukuo. Helion and Company Ltd. ISBN 1-874622-21-3.
• Phillips, S. (2004). The Sino-Japanese War, 1937–1945 : The Military Struggle – Research Guide and Bibliography. Towson University. available on-line
• USMCU CSC (1986). The Soviet Army Offensive : Manchuria, 1945. (US Marine Corps University, Command and Staff College – available on-line)
• Walg, A. J. (March–April 1997). "Wings over the Steppe: Aerial Warfare in Mongolia 1930–1945, Part Three". Air Enthusiast. No. 68. pp. 70–73. ISSN 0143-5450.

Wikimedia Commons has media related to Soviet–Japanese War (1945).

• Japanese Air Order of Battle and Operations Against 'August Storm', August 1945.
• WW2DB: Operation August Storm
• Observations over Soviet Air Arm in Manchurian Strategic Offensive Operation:
  • Aerial actions over Kuriles
  • Soviet Order of Battle
  • Soviet naval aerial kills
• Soviet side information:
  • Comment over Soviet Pacific Fleet during Russian-German Conflict and Japanese forces actions in this period
  • Comment about Soviet Russian Pacific Fleet actions during Manchurian Strategic Offensive Operation
  • General information over Soviet Invasion to Japanese land in Karafuto and Kuriles from August 1945, with some photos, only in Russian language.
• Soviet battle maps:
  • Soviet viewpoint map of the Manchurian Strategic Offensive Operation
  • Soviet viewpoint map of Battle against Japanese fortifications in Shumushu and Paramushiro islands
  • Soviet viewpoint map of Battle against Koton Japanese fortifications in way to Shikuka city, in north Karafuto area
• Japanese POWs:
  • The Notes of Japanese soldier in USSR
• Operation August Storm photo gallery:
  • http://ww2db.com/photo.php?source=all&color=all&list=search&foreigntype=B&foreigntype_id=167
• Japanese in Manchuria and Korea following the war