*** World War II Japan Soviet declaration of war

World War II: Japan--Soviet Declaration of War (August, 1945)

Soviet invsion of Manchurua
Figure 1.--Soviet tanks appears on the streets of the Chinese city of Dalian. Dalien was part of the former Tsarist City of Port Arthur which the Japanese had seized after a priotracted seige in the Russo-Japanese War (1904-05). Located close to the Soviet border, it was one of the first Manchuriancities seized in the Red Army offensive. The reaction of the civilians is interesting. Most do not seem to know what to make of the Red Army tanks. Some of the children seem to be aplauding. Image courtesy of the Military History of the 20th Century website.

The Soviet Union, 2 days after the first atomic bomb was dropped, entered the war against Japan (August 8). Stalin as promised at Yalta and Potsdam declared war on Japan. At the time the Japanese were attempting to use the Soviets to mediate an end to the War. He moved the date up after the Hiroshima bombing because he wanted to be in the War before Japan surrendered. Soviet plans included the invasion of Manchukuo (Manchuria), Mengjiang, Korea, the southern portion of Sakhalin, the Kuril Islands, and Hokkaido. All these operations except the invasion of Hokkaido were carried out. The Soviets struck in Manchuria and routed the Japanese forces there. The offensive was in sharp contrast to the campaigns the Americans conducted in the Pacific. The Soviets after declaring war immediately launched a massive invasion--the largest ground operation of the Pacific War. The Red Army rapidly swept over Manchuria. Japanese resistance crumpled. The Soviet invasion is not well covered in Western histories of the War. One question that arises is why the Soviets so quickly succeeded in Manchuria while the United States struggled in Okinawa. I think this is primarily because Okinawa was a small island where the Japanese could concentrate their forces in mountainous terrain. Manchuria was a huge area, much of it a flat plain, ideal for tank warfare. The Japanese could not defend it like they were able to do on Okinawa. Perhaps readers more familiar with the Soviet invasion will be able to tell us more. Soviet plans included the invasion of Manchukuo (Manchuria), Mengjiang, Korea, the southern portion of Sakhalin, the Kuril Islands, and Hokkaido. All these operations except the invasion of Hokkaido were carried out. The Soviet invasion was called the Manchurian Strategic Offensive Operation. American historian has coined the term 'August Storm', The massive Soviet invasion swept aside Japanese resistance. The Japanese were surprised and destroyed any illusions among the military that Japan's still substantial army had the ability to resist Allied armies. Some authors believe that the success of the Soviets in Manchuria and the inability of the Japanese army to resist them, had more of an impact on the Japanese military than the two American atomic bombs. One factor that we are not yet sure about is why Japanese resistance in Manchuria collapsed so quickly and why the Japanese military commanders were willing to surrender to the Soviets, but unwilling to surrender to the Americans in Okinawa or the Philippines. The Japanese that surrendered to the Soviets spent years in the Gulag. They were used for years in construction projects in Siberia and Central Asia. [Solzhenitsyn, p. 84.] Only about half survived and ever returned to Japan.

Japanese Seizure of Manchuria: Manchuko (1931)

The Japanese Kwantung Army occupied Manchuria, a Chinese province, using as a pretext a faked incident on the main railroad (1931). Japan then declared "Manchukuo" an independent state, setting up Pu Yi, the last Manchu Emperor of China as puppet Emperor (1932). Anti-Japanese disturbances broke out in Shanghai. The Japanese bombed the unprotected city to quell the disturbances. There was no effort to hit military targets. This was the first of many Japanese terror bombings of civilian populations. Japan withdrew from the League of Nations as a resulted of the criticism of her military operations in Manchuria and China (1933). The Japanese encouraged Japanese "colonizers" to emigrate to Manchukuo, but few responded to the propaganda films depicting an Asian paradise. For the Chinese in Manchukuo, life became increasingly difficult.

Russo-Japanese Border War (1939)

The Japanese beginning in 1938 fought a series of engagements with the Soviets along the Manchurian-Mongolian border. A minor border incident (Battle of Lake Khasan) occurred at Primorye (1938). Much more significant engagements occurred the following year. Large scale clashes occurred beginning May 1939 between Japanese and Soviet forces on the Mongolian plains along the border with Japanese-held Manchuria (Manchukuo). Neither side declared war. The Japanese released photographs of captured Soviet soldiers (July 1939). The conflict was little reported in the West. An offensive planned and executed by Marshall Zhukov ended in a decisive victory for the Soviets. The Japanese were forced to seek an armistice (September 1939). The clash was, however, of immense strategic significance, significantly affecting the strategic conduct of World War II. It was undoubtedly a factor encouraging Stalin to respond favorably to NAZI initiatives for a Non-Aggression Pact (August 1939) to ensure that the Soviet Union would not face a two-front war. Hitler ignored the Soviet performance and instead saw the inept Red Army offensive in Finland as evidence that the Soviets could be easily defeated. The Japanese Army concluded that further attacks on the Soviets were unwise. This was an important factor in attacking south in 1941 at America rather than north at the Soviet Union. It was also a major factor in refusing entities from Hitler in 1942 to attack the Soviet Union, freeing the Red Army from what may have been a disastrous two-front war.

Soviet World War II Commitments (1943-45)

Soviet participation in the Pacific War was discussed at all the Big Three Conferences. The Soviet Union committed to entering the Pacific War against Japan, although this was a secret commitment, not part of the joint communique released to the press. At the Tehran Conference (November 1943), Stalin agreed that the Soviet Union would enter the war against Japan once NAZI Germany surrendered in Europe. By this time, progress was being made, but the end of the War still looked remote. At the Yalta Conference (February 1945), the war situation had changed radically and the Germans had been decisively defeated, although the Western Allies had not yet crossed the Rhine. Stalin again agreed to Allied requests to enter the Pacific War. The United States encountered rising casualties as the War moved closer to the Home Islands was anxious for the Soviets to come in as soon as possible. Stalin agreed to enter the Pacific War within 3 months of the end of the war in Europe. Germany subsequently surrender May 8 meaning a Soviet entry by August 8. We are not entirely sure what Stalin's calculation was, but the narrow Trans-Siberian Railway did limit how rapidly the Red Army could transport forces east and the Japanese had a substantial force in Manchuria. At the Potsdam Yalta Conference (July 1945) Stalin again again promised to declare war on Japan. This time the commitment was made to President Truman who had become president after President Roosevelt's death. Truman was staggered by the death tolls on Iwo Jima and Okinawa and was facing the prospect of massive casualties from the planned invasion of the Home Islands--Operation Olympic. While at Potsdam, the atomic bomb was successfully tested. When Truman informed Stalin, he was surprised at the lack of a reaction. We know now this was because Soviet Agents at Los Alamos were keeping the NKVD well informed.

Japanese-Soviet Neutrality/Non-Aggression Pact (1941)

The Japanese Empire and the Soviet Union were bitter enemies as the Manchurian Border War (May-September 1939) had shown. Both countries had, however, strong reasons by 1941 to avoid war. Stalin in signing the Non-Aggression Pact with Hitler had anticipated a war in the West in which the Allies (Britain and France) and Germany would fight a long debilitating war as in World War I. He thought that with these countries weakened that he would be able to expand west. The unexpected collpase of the French Army meant that instead he know faced a triumphannt NAZI Germany without allies or buffer states. Thus defusing the situation along the Siberian-Manchurian border with Japan was very important. The Japanse having decided on the Strike South option also wanted a quiet northern border so they could move south. Thus both countries had strong reason for a diplomatic accomodation. The Neutrality Pact (also called the Non-Aggression Pact) was was signed in Moscow by Foreign Minister Yosuke Matsuoka and Ambassador Yoshitsugu Tatekawa for Japan and Foreign Minister Vyacheslav Mikhailovich Molotov for the Soviet Union (April 13, 1941), Foreign Minister Matsuoka was returning from an Axis conference in Berlin. The Soviet Union committed to respecting Japanese control of Manchukuo (Manchuria). Japan made the same commitment to the Soviet dominated Mongolian People's Republic. The NAZIs did not inform the Japanese of their plan to invade the Soviet Union. And the Japanese did not inform the NAZIs of their plan to sign the Neutrality Pact with the Soviets. This was one of many instances showing the weakness of the Axis Pact. It is difficult to comprehend how Germany and Japan at this crucial moment could have failed to coordinate policy concerning the Soviet Union. The Neutrality Pact remained in force throughout most of the War. The Soviets after the NAZI surrendr in Europe (May 1945) did not automatically renew the Neutrality Pact as the Japanese wanted. The Soviets did not abrogate the Pact, but they did not renew as renewal came due. The pact still had 12 months to run, and the Soviets were not making their policies clear to the Japanese. The commitments made to the llies to join the war against Japan were secret. Soviet diplomats assured the Japanese that they would honor the pact for the next 12 months.

Japanese-Soviet Diplomacy (1939-45)

Japanese foreign policy as World War II approached was strongly anti-Soviet. The Strike North faction wanted to attack the Soviet Union with Germany as an ally. The NAZI-Soviet Non-Aggression Pact (August 1939) undercut this faction, leading to the victory of the Strike South Faction. Japan policy at this time moved toward joining the Axis and convincing the the NAZIs to allow the Soviets to join the Axis to no avail. Hitler at first confident of victory apparently did not want to share the fruits of victory with Japan. After the Wehrmacht was stopped before Moscow (December 1941), he became more interested in Japanese participation. There were, however, no joint strategy session. Germany and Japan pursued entirely separate war policies. The Japanese chose to strike south against the United States rather than joining the Germans in a coordinated war effort. The Red Army's smashing of a Japanese army in a border war may have been a major factor (July 1939). Like Hitler, the Japanese militarists were at first confident of victory over America and Britain. In the last year of the War, the Japanese worked under the illusion that they could obtain Stalin's assistance to seek peace with America. One wonders how they could so misjudge Stalin's character and goals in Asia. A reader insists that the Soviets "... were putting a LOT of effort into deceiving them, and assuring them that the Soviets would indeed assist them." [Fisher] It is certainly true that Soviet diplomats led the Japanese along. There were plenty of indicators, however, that the Soviets were not going to be helpful. The fact that there was a neutrality pact was meaningless. he Soviet Union invaded virtually every country they bordered, except Turkey, Afghanistan, and China. And one included Poland with which they had a Neutrality Pact. They also were aware of traffic on the Trans-Siberian Railway, although they believed that the Soviets were not yet ready to invade. There were plenty of clues that should have shown the Japanese that they could not rely on Stalin to interceded with the Americans, After the tide of the War changed, Stalin began making public statements that showed hostility to Japan. Japanese diplomats in Moscow had increasing difficulty making appointments with Soviet officials, even when they began offering territorial concessions. The failure to renew the Neutrality Pact. (While as you say it was not abrogated, still it was not a positive sign. The lack of any actual steps to interceded with the Americans. The withdrawal of Soviet diplomats from Japan. All of these were clear indicators. Ambassador Sato in Moscow had difficulty even meeting with Soviet officials informed Tokyo, but the Foreign Ministry lacking any other options but surrender continued to press him to seek Soviet good offices to end the War. The Soviet abrogation of the Neutrality Pact (April 1945) should have told the Japanese Foreign Ministry where the Soviets were headed. Stalin did not pass on these feelers to the United States, largely because he did not want the War to end before he could send the Red army into Manchuria.

Soviet Denuciation of the Neutrality Pact (April 1945)

The Japanese-Soviet Neutrality Pact signed in 1941 was a 5-year agreement meaning it ran into 1946. It could be ended earlier with 1-year notice. After the Yalta Conference and before the NAZI surrender, the Soviet Union moved to allow the Neutrality Pact with Japan to lapse. Foreign Minister Molotov summoned Ambassador Sato to the Foreign Ministry and delivered the following statement (April 5, 1945). "The neutrality pact between the Soviet Union and Japan was concluded on April 13, 1941, that is, before the attack of Germany on the USSR and before the outbreak of war between Japan on the one hand and England and the United States on the other. Since that time the situation has been basically altered. Germany has attacked the USSR, and Japan, ally of Germany, is aiding the latter in its war against the USSR. Furthermore Japan is waging a war with the USA and England, which are allies of the Soviet Union. In these circumstances the neutrality pact between Japan and the USSR has lost its sense, and the prolongation of that pact has become impossible. On the strength of the above and in accordance with Article Three of the above mentioned pact, which envisaged the right of denunciation one year before the lapse of the five-year period of operation of the pact, the Soviet Government hereby makes known [sic] to the Government of Japan its wish to denounce the pact of April 13, 1941." Theoretically the Neutrality Pact remained in force for another year, the 5-year duration and the 1-year notice ending at aboiut the sane time--April 1946. Ambassador Sato subsequently attempted to open negotiations for a renewal. Soviet officals did not flatly refuse, but did not commit to any such negotiations.

Manchuria and Korea: Importance

Manchuria and Korea were important sources of both food and raw materials supporting the Japanese war effort. Japan is a resource-poor country. They had launched the War to obtain food and raw materials. By the final year of the War, they were back to the colonies they possessed before they launched the War. The Amrican submarine campaign had cut the Japanese off from their Southern Resource Zone (SRZ) and destroyed much of the Maru fleet. The resurgent Pacific Fleet tightened the blockade (1944). Virtually the only source of both food and raw materials available to the Japanese were Manchuria and Korea. Shipments from both Manchurua and Korea were still possible because of the short distances and the fact that the Sea of Japan was still relatively secure, even after Okinawa fell (April 1945).

Soviet Intentions

Stalin had vast strategic goals in the Far East. The Russo-Japanese War (1904-05) had seriously reduced Russia's Far Eastern position, especially in Manchuria and Korea. His calcultion at the time was based on the fact that China, the rightfull owner of Japanese occupied Manchuria was a non-Communist Government, albeit a member of the Allied coalition. As part of his psyche, he was determined to regain territory of the former Tsarist Empire. Stalin now saw an opportunity to gain lost territory and economic concessions. He wanted the rail and base rights in Manchuria that had been lost to Japan. Other goals included consolidating the Soviet position in Mongolia. In addition he wanted full control of Sakhalin and the Kuril Islands. The Soviet Government made nine of its inhtentions clear. Foreign Minister Molotov after the NAZI surrender and V-E Day reinterated that the Neutrality Pact was still in force. He told Ambassador Satō, "We have not torn up the pact." Soviet Ambassador Malik repeated the sanme message several times, but was not informed of his goverbment's plan to attack the Japanese in Matchuria. [Slavinskiĭ, p. 184.]

Soviet Buildup (May-July 1945)

Stalin was understandably wary of Japanese intentions as Germany and Japan were Axis partners. Stalin maintained about 40 divisions on the Manchurian frontier throughout the war (1941–45) despite the desperate fighting on the Eastern Front. Some Siberians reserves were brought west for the Red Army offensive before Moscow (December 1941), but Stalin maintain potent forces on the Manchurian border throughout the War. As the Red Army drove in the Berlin and the NAZIs teetered on collapse, Stalin began shifting forces east (April 1945). The redeployment was designed to doubled the number of Soviet forces in the Far East to 80 divisions. The Red Army shifted more than 40 divisions from East Prussia and Czechoslovakia in the heart of Western Europe to the Mongolian and Siberia frontier areas bordering Manchuria (May-July 1945). It was a relatively slow process because of the limited capacity of the Trans-Siberian Railway. Even so some 22–30 trains a day moved forces east. Much of this was done at night to maintain security. Assembly areas were established at some distance from the border. Other security measures were instructing senior Red Army officers not to wear rank insignia. The 6th Guards Tank Army left their tanks and other heavy equipment behind in Czechoslovakia. They acquired new equipment manufactured by the Soviet Urals arms factories. [Glantz] Red Army military doctrine firmly supported by Marshall Zhukov was to build up an overwhelming superior force before striking. And with the German surrender, massive forces were available for an offensive in the east against Japan. A major constraint was the limited capacity of the Trans-Siberian Railway, the only way of transporting the men, supplies, and heavy equipment needed for the offensive. Marshal Vasilevsky reported to Stalin (August 3) that his forces were ready and, if necessary, he could attack on the morning of August 5.

Japanese Preparations

Imperial Japanese Army Headquarters instead of preparing for a Soviet invasion instead withdrew substantial forces from Manchuria. Their concern understandably was for the defense of the Home Islands and preparing for the coming American invasion. They thus withdrew most of the strongest formations, including armor and elite infantry, from the Kwangtung Army. Also among the forces withdrawn were air assetts. They were intent on building up a secret air force to launch massive Kamikazee attacks against the Allied invasion fleet. At its peak, the Kwangtung Army had over 1 million well trained and equipped men. Thus the Japanese forces facing the Soviet border areas were substantially reduced. The Japanese in Manchuria had to alter their defensive battle plan. The new Japanese 1945 plan called for fighting a delaying action along the border and withdrawing to prepared defensive lines established as a stronghold in southeastern Manchuria for a final defensive battle. The Japanese lacking good intelligence made some serious errors, especially about terrain believed to constrain Red army operations. The Japanese assessment was that the western borderlands could not be crossed with heavy equipment. The vast Mongolian desert and the Grand Khingan Mountains were believed to be a impassable natural barrier. Their intelligence included some monitoring of Trans-Siberian Railway. They apparently detected Red Army build up, but misjudged the speed and dimensions. Imperial Army Headquarters had concluded that the Red Army could not yet carry out large-scale combined-arms assaults because of logistical constraints. [Glantz]

Atomic Bombs

The American Manhattan Project was launched out of fear that NAZI Germany was building atomic weapons. German cities were reduced to rubble and The NAZIs surrendered before the bomb could be used in Europe. The bomb was successfully tested (July 1945) just as the Americans were beginning preparations for a invasion of the Home Islands. The casualties on Iwo Jima and Okinawa and the Japanese commitment to fight to the death was horrifying. Some experts estimated that there may be as many as a million American casualties. President Truman issued a warning at the Potsdam Conference. When the Japanese failed to respond., he authorized the use of the new weapon on Japan. Many sources suggest that the American Hiroshima attack caused Stalin to advance his schedule. He order the immediate declaration of war on Japan and invasion of Manchuria least Japan surrender before the Soviets attacked. Other sources point out that the invasion began on August 9, 1945, precisely 3 months after the German surrender on May 8 (May 9, 0:43 Moscow time). The Hiroshima attack thus does not appear to have played a Major role in the timing of the Soviet declaration of war. The Soviet invasion fell between the atomic bombings of Hiroshima (August 6) and Nagasaki (August 9.). Truman informed Stalin about the successful A-Bomb test in New Mexico, but did not provide much in the way of detail. Soviet intelligence agents had provided much more information. Stalin does not seem very impressed with ether Truman's notification or intelligence reports. Once details on the power of the two bombs reached Stalin, he was duly impressed. Stalin ordered the Soviet atomic program be given a major priority.

Soviet Declaration of War (August 8, 1945)

The Soviet Union, 2 days after the first atomic bomb was dropped on Hiroshima, entered the war against Japan (August 8). At the time the Japanese were still desperately attempting to use the Soviets to mediate an end to the War. Soviet Foreign Minister Molotov informed Japanese Ambassador Sato that the Soviet Union had declared war on the Japanese Empire (11pm Trans-Baikal time on August 8, 1945). Molotov told Sato that from August 9 the Soviet Government would consider itself to be at war with Japan. This was 2 hours before the actual invasion of Manchuria. They did not, however, transmit Ambassador Satō's cable notifying Tokyo of the declaration of war, despite assurances that they would. They also cut the embassy phone lines. This was apparently in Stalin's and Molotov's mind revenge for the Japanese sneak attack on Port Arthur which launched the Russo-Japanese War 40 years previously. The Japanese Government learned of the declaration of war from a Moscow radio broadcast as well as reports from their military ouposts in Manchuria. [Butow, pp. 154–164].

Soviet Offensive (August 9)

The Red Army prepared a massive invasion plan. Soviet plans included the invasion of Manchukuo (Manchuria), Mengjiang, Korea, the southern portion of Sakhalin, the Kuril Islands, and Hokkaido. All these operations except the invasion of Hokkaido which would have required a massive invasion flotilla were swiftly carried out. The Soviet name for the invasion, at least the Manchurian phase of it, was the Manchurian Strategic Offensive Operation (Манчжурская стратегическая наступательная операция). An American historian later coined the term 'August Storm'. [Glantz]. The Red Army commenced the invasion simultaneously on three fronts to the east, west and north of Manchuria (one minute past midnight Trans-Baikal time on August 9, 1945). The massive Soviet invasion swept aside inefectual Japanese resistance.

Manchuria (August 9)

The Soviets struck in Manchuria and routed the Japanese forces there. This is perhps the most pootrly reported campaign of World War II. This is because the Japanese documents captured by the Sovits are still held as secret by the Russians. And almost all of the major Japanese commanders did not survive the Soviet Gulag. The Red army launched a classic double envelopment of Japanese-occupied Manchuria (August 9). These were the Blitzkrieg tactics first the Wehrmacht and then the Red Army had perfected on the Eastern Front. The result was a series of lighting attacks carried out on three axes over a 3,000-mile front. One historian describes this as a graduation exercise for the battle-hardened and increasingly competent Red Army. [Glantz] The Japanese defensive plan was based on controbting two Soviet Army Fronts (Groups). To the East (Vladivostok Front) and the North (Mongolia Front). They did not prepare for a third front and did not expect an attack in the west because of the barrier of the Gobi Desert and the Greater Khingan Mountains. The Soviets after declaring war immediately struck all across the front,kincluding in the west. They launched a massive invasion--the largest ground operation of the Pacific War. The Red Army rapidly swept over Manchuria. Japanese resistance crumpled. The Soviet invasion is not well covered in Western histories of the War. In terms of manpower, the Red Army had only a slight advantage. Their men were, however, veterans of the war against the Germans and were skilled in and equipped for modern, mobile war. The Japanese in contrast were a largely untested occupation force. The Soviets struck in the west with a masive force of T-34 and almost indistructable KV tanks supported by Mongolian horse calvalry. This force was supplied by air drops of fuel and hay from Soviet aircraft. The Japanese Kwantung Army in Manchuria was as a result routed the Japanese in only 2 weeks. The Japanese were facing 2 Soviet Army fronts The offensive was in sharp contrast to the campaigns the Americans conducted in the Pacific. There is a the difference between putting up a stiff and costly defense of a well prepared island garrison who had plenty of time to build numerous underground bunkers and a tunnel network. One question that arises is why the Soviets so quickly succeeded in Manchuria while the United States struggled in Okinawa. We think this is primarily because Okinawa was a small island where the Japanese could concentrate their forces in mountainous terrain. Manchuria was a huge area, much of it a flat plain, ideal for tank warfare. The Soviets after massive tank battles with the Germans were experts in tank warfare and had the superb T-34. The Japanese had a substantial tank force in Manchuria, but much smaller than the Soviet armored force. And the Japanese tanks were some of the worst deployed by any major belligerent countries. Compared to the Soviet tanks, the Japanese tanks were tin can death traps. The biggest problem for the Soviets was to make sure their anti-tank rounds exploded in the Japanese tank and not after passing through and coming out the other side. The Japanese tanks were basically the same ones they had all through the war and were designed by the Army for fighting the Chinese Army of 1937 which did not have tanks or anti-tank guns. Not the Soviet T-34s. The Soviets also had great advantages in artillery and aircraft. The Japanese could not defend Manchuria like they were able to do on Okinawa. Red air Force units were able to easily establish air superiority. The Japanese preparing for an American invasion had withdrawn much of their air assets. This allowed the Red Army to take substantial risks. They dropped battalion-size formations which moved on major cities in southern Manchuria. They also seizing communications centers, especially Harbin, disrupting Japanese command and control. [Glantz]. The Japanese in Okinawa as in Iwo Jima knew their role was to make it as costly to the US as possible while fighting to the last man. They knew they were not coming home and all through the war the Japanese military were versed on the idea of no surrender; fight to the last man. In Manchuria they did not have a chance. As you wrote vast amounts of Japanese forces were quickly surrounded and just were not capable of fighting to the last man because they were over run so quickly. Some Japanese settlers committed suicide as the Red Army approached. There were reported incidents of mass suiside. Parents killed their children before killing themselves. The Japanese army apparently took part killings their own civilians.


Mengjiang is virtually unmentioned in Western histories. It is also know as Mongol Border Land. It was an autonomous area of Inner Mongolia. It was an area of the Steppe nominally controlled by China adjacent to Soviet controlled Mongolia. The Japanese after seizing Mongolia (1931), tuned it into a puppet state, at first maintaining the fiction of Chinese sovereignty. The Japanese formed a military government (蒙古軍政府) in Mengjiang (1936). Prince Yondonwangchug of Ulanqab was the first chairman. The Japanese after invading China proper, remamed Mengjiang the Mongol United Autonomous Government (蒙古聯盟自治政府) (1937). The Japanese then merged the mostly Han Chinese provinces of South Chahar and North Shanxi were merged with the Mongol United Autonomous Government, creating the new Mengjiang United Autonomous Government (蒙疆聯合自治政府) (1939). The capital was located at Zhangbei (Changpei), near Kalgan (Zhangjiakou). The government from the beginning as a Japanese fiction, only maintained by te Japanese Kwantung Army. The government's control was primarily located in the cities. The Japanese reamed it again as the Mongolian Autonomous Federation (蒙古自治邦) (1941). After Japanese Wang Jingwei formed a new collaborationist Chinese Government in Nanjing, Mengjiang was nominally placed under his control. It fact it was autonomous under the control of the Kwantung Army. The Soviet Red Army with Mongolian units participating invaded Mengjiang as part of Stalin's Manchurian Strategic Offensive Operation (1945). Most of the area except Kalgan, is now part of Inner Mongolia in the People's Republic of China.


Korea had been a Japanese colony since 1909. There were, however, no prepared defenses. After seizing Manchuria (1931), the Japanese dod not anticipate an attack from the north. The Japanese concripted Koreans for labor brigasdes durung the Pacific SWar, but nor for combat units. To do so woukld have pfrivided mikitary training for a subject and basically histile people. The Japanese realized that the Soviets might attack, but despite the massive Soviet build up, do not appear to have made major defensive preparatrions. They reralised, howeever, in case of attack that they had no ability to hold Manchuria. Their basic plan was to resist the Soviet offensive in the east and north and to conduct a fighting wirhdraw and to establish a firm front on the Yalu River, the demarlation point between Manchuria and Korea. An attack in the west from Mnchurua was seen as less likely. With the Yalu brrier and the narrow with of the Korean Peninsula to the south the Japanese believed thst they could hold off the Soviets. This plam becne unglued from the very beginning. he Japanese had no air cover. The advancing Soviets thanks in pat to American trucks were much more mobile than the retreating Japanese, meaning large Japanese elements were cut off and surrounded. Superior Soviet tanks and artillery meant that the Soviets pierced the Japanese lines at virtually any point they chosse. And the Soviet attack from the west faced virtully no Japanese resistance, As aesult, Soviet forces got to the Yalu in force before the retreating Japanese did. The Red Army conducted amphibious assaults in modern-day North Korea to interdict Japanese sea lines of communication across the Sea of Japan. [Glantz]

Sakhalin (August 11)

The northern island of Sakhalin wa long disputed between the Japanese and Russian Empires. There were o major confrontations. The Russians had only limitedmeans in the Far East which s why they sold alska to the United states. Still feudal Japn had no way of projecting pwer to the far north. As a result of the Russo-Japanese War (1904-05), Japanese gained control over the southern half of the war. The island was split at the 50th parallel. The Japanese called it the Karafuto Prefecture and the Northern District. This meant that unlike the Japanese Home Islands, there was no naval impediment to the Red Army seizure of the southrn half of the islad after declaring war. At the Yalta Conference, eager to obrain Soviet assistace in the Pacific War, the United tates agreed to Soviet seizure of south Sakhalin and the Kuril Islands among other concessions. The United States agreed to assist the Soviet Red Army in Project Hula in the operation. The Soviet invasion of Manchura included an operation in Sakalin (1945). The Soviet 16th Army lauched the ground invasion of southern Sakhalin (August 11). The of the southern portion of Sakhalin Island controlled by Japan. The Soviet advance was stopped at the well-prepred Japanese defense line centered on the Karafuto Fortress. The Soviet 16th Army had some 20,000 men and 100 modern tanks. The Japanese force was only a third of the attacking Soviet force, but they managed to hold the Soviets back for 4 days on the Karafuto line. By this time, the Emperor had broacast his surrender declaration and Imperial Japanese headquarters ordered the Japanese commander to halt all offensive combat operations and open cease-fire talks (August 15). The Japanese 5th Area Army commander rejected the surrendr. He issued ordes to the 88th Division to defend Sakhalin to the last man. Some 3,000 Japanese troops surrendered at the Karafuto Line. The Soviet Red Navy launched an amphibious assault operation to the south against the key ports. This operation was, howeeer, limited by the smll Soviet naval capabilities. They also organized a naval blockade of Sakhalin. There was no Japanese effort to reinforce the island, but the Soviets were intent on preventing the evacuation of Japanese troops. In fact they also targeted civilian evacuations. Civilian convoys were targeted by Soviet submarines in the Aniva Gulf.

Kuril Islands (August 18)

Stalin wanted to share in the occupation of Japan of Japan in the same way that the occupation of Germany was unfolding. While he had assembeled a massive force in the Far East and used it to invade Mnchuria and Korea (August 9). Invading Japan, however, was a very different matter. The Soviets did not have the sea-lift capability of getting part of its Far East forces to the Japanese Home Islands. The Soviet Manchurian Strategic Offensive Operation included plans to invase Hokaido, the norther Japanse Home Island. It soon became apparent that the limited Soviet Sea-Lift capability made this impossible. Instead they conducted a an opeation to seize the much smaller Kuril Islands extenting from Japan's Hokaido in a northerly arc to the Soviet Kamchatka Peninsula. The only battle of the Soviet campaign was the Battle of Shumshu. This was to be the beginning of a Soviet effort to seize the Kuril Islands and hopefully northern Japan. It proved to be the only major battle of the Soviet Kuril campaign and one of the last battles of the War. The United Statrs as the war wound down in Europe pressed Stalin to enter the Pacific War agint Japan. Stalin wanted to do just that, but his desire to do so. He agreed to do so only after the Grmans surrendered abd then with a-month lag time to transer forces east. He also demanded Lend Lease aid for his Pacific forces. The United States complied, including transfering a dozen types of ships and aircraft to the Soviets. The United States secretly transferred 149 ships and aircraft (Spring-Summer 1945). They included vessels needed for amphibious operations. Most were escort vessels, landing craft, and minesweepers (Spring-Summer 1945). The transfer occurred at Cold Bay in Alaska and was named Project Hula. [Russel, p. 8.] Some historians argue that President Truman because of problems dealing with the Soviets in post-War Germany was not interested in a joint American-Soviet occupation of Japan. [Hasegawa] Soviet landings began (ugust18). The Soviets encountered considerable resitance, largely because of their limited naval capability making it impossibl to move a subtantial force to Shumshu. As a result there was no fighting further south. Victory came only when the Japanese Goverment convined their forces on Shumshu to cease reistnce (August 23). The Soviets encounterd no further resistance in its seizure of the Kuril Islands (completed by September 1). The Soiviets given the levl of resistnce on Shumshu and their limited sea-lift capoability abandoned plans to invade Hokaido.


Stalin wanted Hokkido, the northern most Home Island. Unlike Sakalin ad the Jurile Islnds, however, it wa not promised to him at Yalta. And it was much more heavily defended than Sakalin and the Kuriles. Nor did the Imperial Government order Japanese troops on Hokkaido cease offensive opertions or open cease-fire talks with the Soviets. All the Soviet invasion operations were carried out with the exception of the the invasion of Hokkaido. There is no doubt that the Red Army could have defeated the Japanese forces on Hokkaido id there had been aand connection. But there was no not. An amphibious operation against a substantial eneneny force is a complicated operation requiring an importnt naval force to land forces, support them, and bring in reinforcements and supplis. This was far beyond the capabilities of the Soviet Red Naby no matter how stringly Stalin willed it. Given the difficulties experienced in the first Kurile assault and the limited naval forces available, even Stalin was forced to admit that the Red Army just did not have the cpabality to land forces on Hokkaido and engage a substantial Japanese defense force.

Japanese Reaction

The Japanese were surprised with the Soviet invasion. Here the reaction varied. Some Japanese diplomats did think that the Soviets would help intercede with the Americans. Others were surprised by the timing of the Soviet invasion. The Soviets It destroyed any illusions among the military that Japan's still substantial army had the ability to resist Allied armies. Of course the flat Manchurian plain was perfect for Soviet armored warfare. The mountainous terrain if the Home Islands would have proved more difficult. One reader tells is, "The Japanese were surprised how quickly they were defeated. They were not surprised that they were defeated." [French] Some authors believe that the success of the Soviets in Manchuria and the inability of the Japanese army to resist them, had more of an impact on the Japanese military than the two American atomic bombs.


One factor that we are not yet sure about is why Japanese resistance in Manchuria collapsed so quickly. The oerwealming superiority of Soviet forces and the flat terraine of mjuch of Manchuria certainly were factors. What we do not understand is why the Japanese military commanders were willing to surrender to the Soviets, but unwilling to surrender to the Americans in the Philippines, Iwo Jima, and Okinawa. The Japanese soldiers that surrendered to the Soviets spent years in POW camps anhd the Gulag. They were used in construction projects in Siberia and Central Asia. [Solzhenitsyn, p. 84.] Only about half survived and ever returned to Japan. While horrendous, it was a higher survival rate than was the case iof German POWs held by the Soviets.


Butow, Robert J. C. Japan's Decision to Surrender (Stanford University Press: 1954).

Fisher, Peter. E-Mail message (June 28, 2013).

Glantz, David M. Soviet Operational and Tactical Combat in Manchuria, 1945: August Storm (Frank Cass Publishers: 2004).

Slavinskiĭ, Boris Nikolaevich. The Japanese-Soviet Neutrality Pact: A Diplomatic History, 1941–1945 Nissan Institute/Routledge Japanese studies series. (Routledge Curzon, New York, 2004).

Solzhenitsyn, Aleksandr I. The Gulag Archipelago (Harper & Row: New York, 1973), 660p.

Van Nederveen, Giles.

Military History of the 20th Century website.


Navigate the CIH--World war II Section:
[Return to Main Japanese surrender page]
[Return to Japanese-German strategic concepts page]
[Return to Main Japanese World War II page]
[Return to Main World War II Pacific campaign page]
[Biographies] [Campaigns] [Children] [Countries] [Deciding factors] [Diplomacy] [Geo-political crisis] [Economics] [Home front] [Intelligence]
[Resistance] [Race] [Refugees] [Technology]
[Bibliographies] [Contributions] [FAQs] [Images] [Links] [Registration] [Tools]
[Return to Main World War II page]
[Return to Main war essay page]

Created: 8:02 AM 9/13/2012
Spell checked: 5:31 AM 6/29/2013
Last updated: 4:15 PM 7/12/2019