Nov. 29, 2025, 7:53 p.m.
(The Soviet offensive. PHOTO: https://warfarehistorynetwork.com/)
World War II was a terrible period in human history. The frightening thing about this seven-year-long confrontation is not only the number of dead, but also the level of cruelty towards representatives of other nations. In Soviet literature, it was generally believed that the war actually ended in May 1945. In fact, the war lasted for almost four months, and this period contained a lot, including subtle political intrigues, active hostilities, and new manifestations of cruelty. In this article, the author of Intent focuses on the confrontation between the USSR and Japan in August-September 1945 and reflects on how much the Soviet intervention accelerated the end of the world war.
In the last quarter of the nineteenth century and four decades of the twentieth century, Japan and the Russian Empire (later the USSR) fought a fierce confrontation for dominance in Northeast Asia. After the launch of reforms in the late nineteenth century, Japan quickly began to emerge as one of the leading powers in the world. However, the Japanese regional ambitions clashed with the interests of the Russian Empire. Both countries tried to take advantage of the decline of China, which became the main donor of their ambitions.
The main clashes took place in the twentieth century. Initially, the Japanese gained the upper hand. They won the Russo-Japanese War of 1904-1905, later annexed Korea, intervened in the Far East after the overthrow of the Russian Empire, and in the early 1930s seized Manchuria. However, in the late 1930s, the USSR successfully took revenge on Lake Hassan and Halkhin Gol: Japan at that time was involved in a war with China and could not effectively fight on two fronts.
In the second half of the 1930s, Japan was at the crossroads of two militaristic plans. One plan was to attack the USSR and develop its expansion to the west, while the other was to move southeastward, attacking European colonies and the Pacific region. Presumably, the defeat of the USSR was to finally direct the Japanese in the second direction, but it was necessary to obtain guarantees that the USSR would not attack in the back. At this point, the USSR was also concerned about the possibility of a two-front war. Although the Molotov-Ribbentrop Pact was signed with Germany, the prospect of war seemed inevitable. Therefore, on April 13, 1941, the USSR and Japan signed a neutrality pact, which, as the following months showed, benefited the Bolsheviks much more than their eastern partners. Article 2 of the Pact was of key importance. According to it, if one of the signatories to the Pact enters a war, the other must stay out of the conflict. It was important that the agreement was signed for five years with the possibility of extension. To terminate the agreement, one had to give the other party a year's notice.
One of the key episodes of World War II was the Battle of Stalingrad, which represented a certain turn in the confrontation and hinted at the possibility of a still distant victory. One way or another, at the Tehran Conference in late 1943, Stalin promised Churchill and Roosevelt that he would be able to join the war against Japan after the victory over Germany. In early 1945, it was already obvious that Germany was doomed. And at the Yalta Conference in February, the leaders of the USSR, the United States, and Britain signed an agreement stating that the USSR would enter the war with Japan no later than 3 months after Germany's defeat. Of course, the USSR did not agree to a new war for altruistic reasons. In exchange, the Allies promised the Bolsheviks, among other things, the southern part of Sakhalin Island, the Kuril Islands, the status of an independent state for Mongolia, and the renewal of the lease of Port Arthur.
Churchill, Roosevelt, and Stalin in Yalta. PHOTO: Wikipedia
As the war with Germany was moving toward victory, in March 1945, Stalin began to deploy some combat units to the Far East. On April 5, a year before the expiration of the Neutrality Pact, the USSR informed Japan that it would not extend the treaty. For Japan, this was an alarming signal on the diplomatic field. However, the Bolsheviks assured the Japanese that they would fulfill their obligations under the Pact until April 1946.
On May 8, 1945, Germany signed the surrender, which activated the three-month period for the USSR to enter the war with Japan. Undoubtedly, Stalin intended to enter the war, as it would lead to territorial gains and increased prestige for the USSR. However, he wanted to do so with maximum comfort. First, each new week of the war in the east exhausted the Japanese army and lowered its morale. On the other hand, the Red Army was getting more time to redeploy troops from the European fronts. Secondly, Stalin wanted to take the Japanese by surprise so that they would not realize the attack until the last moment. To this end, troops were gradually redeployed to the east in separate groups. In the diplomatic field, Stalin flirted with the Japanese, giving them hope that a deal could be reached at the right price. In particular, at the Potsdam Conference in late July, a declaration was issued demanding Japan's unconditional surrender. The document bore the signatures of representatives of the United States, Britain, and China, but no signature of Stalin. In this way, the USSR was letting the Japanese know that the window of opportunity for a deal was supposedly open.
In 1941-42, Japan took control of almost all of East Asia and a vast territory in the Pacific Ocean that stretched to the coast of Australia. In the following years, things did not go so well: the Japanese tried to preserve what they had achieved and gradually began to lose the territories they had gained. In 1945, the negative trends for Japan continued to grow as the resistance of the Nazi bloc countries in Europe weakened.
Japanese expansion in 1941-1942. MAP OF JAPAN: Wikipedia
The main Japanese force in mainland Asia was the Kwantung Army, which was located in Manchuria. This army was considered an elite group that had been hardened in the battles of 1930-1940. This army had such authority that it sometimes allowed itself to make decisions contrary to the central government. However, the main theater of operations for Japan was not the mainland, but the Pacific Ocean. Therefore, the Kwantung Army was forced to give up experienced soldiers and equipment to the Pacific units.
In the spring of 1945, it became obvious to the Japanese that an attack by the Soviets was only a matter of time. Therefore, they began preparing a system of fortifications on the borders with the USSR and replenishing the Kwantung Army. From a quantitative point of view, the manning was successful. However, the numbers in the sources vary greatly. Russian and Ukrainian sources mostly point to 700,000 soldiers, while English-language sources point to about 1 million soldiers. A significant number of the new recruits were recruited from young people who did not have sufficient experience and partially fit older Japanese. The Kwantung Army's military equipment was outdated, having been developed in the 1930s. For example, Japanese artillery was effective only against light Soviet tanks. In addition, the Bolsheviks had a significant quantitative technical advantage. For example, the USSR had a fivefold advantage in tanks and artillery, and a twofold advantage in the air.
Starting in April 1945, Japan tried to establish diplomatic contact with the USSR. Since the Japanese were losing ground on the front, they hoped that the neutral USSR would be able to mediate in negotiations with the United States and Britain. At the same time, Japan was ready to make territorial concessions in favor of the USSR. Even in such a difficult situation, the Japanese did not lose their fighting spirit. The main danger was the opening of a second front by the USSR.
By the beginning of August, the USSR had actually doubled its grouping in the Far East, bringing the total number of soldiers to 1.5 million. Some say that the date of the attack on Japan was set for August 15. Other sources indicate that the attack was to take place between August 20 and 25. However, on August 6, the United States dropped an atomic bomb on Hiroshima. The use of the most terrible weapon in human history by the Americans could have led to Japan's premature surrender, and the USSR might not have received its share of the Far Eastern pie.
The United States drops an atomic bomb on Hiroshima. PHOTO: h ttp://j i.lviv.ua/
On August 8, at 17:00 Moscow time, People's Commissar for Foreign Affairs Vyacheslav Molotov told the Japanese ambassador that the two countries would be at war from August 9. The nuance of the message was that, according to Japanese time, there was about an hour left before the start of hostilities. At the beginning of the first hour of the new day, Soviet troops went on the offensive. Approximately 11 hours after the start of the Soviet invasion, the United States dropped an atomic bomb on Nagasaki.
The Soviet forces were divided into three fronts. The Trans-Baikal Front, led by Marshal Rodion Malinovsky, was to attack Inner Mongolia from the west; the 1st Far Eastern Front, led by Marshal Kirill Meretskov, was to attack from the east from Soviet Primorye; the 2nd Far Eastern Front, led by General Maxim Purkayev, was to attack from the north. The essence of the operation was to encircle the Kwantung Army on a territory of 1.5 million square kilometers (approximately 2.5 times the territory of Ukraine). The attacks from the east and west were to converge in Changchun, the conditional center of Manchuria.
Map of the Soviet attack on Japan. PHOTO: Wikipedia
The Japanese prepared for the Soviet attack, but expected it later. August is the rainy season in Japan, which is unfavorable for military operations. They expected the Bolsheviks to attack in the fall. The Japanese believed that they would not be able to retain Manchuria under Soviet pressure, so they planned to retreat to Korea in an organized manner with battles, where they would hold a bridgehead. However, due to an unexpected attack, some Japanese commanders found themselves outside their units at the beginning of the invasion.
The operation began with Soviet bombers striking targets in Changchun and Harbin. For several days, the Red Army's aviation bombed communication lines, making it much more difficult for the Japanese to defend themselves. The Soviet troops advanced at a frantic pace: in some areas, they covered up to 150 kilometers in the first day. The Trans-Baikal Front advanced through the Mongolian deserts and reached the Great Hingan mountain range, beyond which flat terrain opened up.
Soviet equipment advancing. PHOTO: https://warfarehistorynetwork.com/
The 1st Far Eastern Front simultaneously broke through the Japanese border fortifications in the east. The troops of the 2nd Far Eastern Front crossed the Amur and Ussuri rivers and overcame the Little Hingan mountain range.
The Japanese are waiting for an attack. PHOTO: https://warfarehistorynetwork.com/
At the first stage, Soviet troops did not encounter systematic resistance from the Japanese. Rather, the main obstacles were the terrain and weather. Within a few days, the Red Army's equipment began to run out of fuel, as supply units could not keep up with the pace of the main forces. To solve the problem, fuel was flown in by airplanes. Some units began to abandon Sherman tanks, which required a lot of fuel.
In some areas, the Japanese still put up fierce resistance. In particular, on the left flank of the Trans-Baikal Front, Soviet troops failed to capture the city of Hailar on the march, which was defended by Japanese troops with the support of Manchurian cavalry. On August 10, Soviet troops took the suburbs, but the Japanese held the city center. Having regrouped their forces, the Soviet troops eventually drove the enemy out of Hailar, but the Japanese took key positions around the city, preventing the Red Army from taking control. The Japanese surrendered Hailar only on August 18.
The southern group of troops of the 1st Far Eastern Front was ordered to take control of the northern part of the Korean Peninsula. The Red Army planned to capture the main cities of the region, including strategically important ports that connected the peninsula with the metropolis. For several days, the battle for the port and industrial center of Sejin was fought, which was stormed by Soviet landing forces supported by marines and naval artillery landed from ships. The rapid Soviet advance in Korea frightened the United States, so on August 10, they offered the USSR to divide Korea along the 38th parallel.
The landing of Soviet troops. PHOTO: Wikipedia
The efforts of the 2nd Far Eastern Front and the Pacific Flotilla successfully captured the Kuril Islands and the southern part of Sakhalin Island. The USSR's appetites grew as the operation progressed, and Marshal Alexander Vasilevsky, Commander-in-Chief of Soviet troops in the Far East, even developed a plan for an operation to land on the Japanese island of Hokkaido. However, Stalin's proposal to the United States to divide Japan according to the German model did not find support, and the USSR did not want to spoil relations with Washington at that time.
The landing on the island of Shumshu. PHOTO: Wikipedia
On August 4, the Japanese authorities approached the Allies with a proposal to discuss the terms of surrender. On the same day, Emperor Hirohito asked the Japanese army to cease fire until further notice. However, some Japanese officers regarded the order as treasonous and continued to fight. The defeat of the Kwantung Army was officially announced on August 18. On September 2, 1945, Japan signed the Act of Surrender, ending World War II. At the same time, some military clashes continued until September 10.
The signing of the Japanese Surrender Act. PHOTO: h ttp://j i.lviv.ua/
After the end of the conflict, the USSR gained the Kuril Islands, the southern part of Sakhalin Island, and regained control of Port Arthur. In addition, Mongolia retained its independence, and Korea was divided into North and South Korea. In the San Francisco Peace Treaty of 1951, Japan gave up the southern part of Sakhalin and the Kuril Islands, but in no treaty did it indicate that it had transferred them to the USSR. Because of this legal incident, Japan is still demanding that Russia return the southern Kuril Islands.
The USSR navy flag in Port Arthur. PHOTO: Wikipedia
According to Soviet official sources, 84,000 Japanese were killed in the conflict and almost 600,000 more were taken prisoner. The USSR estimated its own losses at about 12,000 killed and 24,500 wounded. Japanese prisoners were mostly sent to Soviet camps. By doing so, the USSR violated the Potsdam Declaration, according to which prisoners of war were to be sent home. According to various estimates, 60-80 thousand Japanese died in captivity. The last Japanese prisoners of war were released from the camps only in 1956.
In Manchuria, the Soviet military dismantled industrial equipment in violation of international treaties and took it to the USSR. The Red Army destroyed what could not be exported so as not to leave it to the official capitalist authorities of China. As in the territory of occupied Germany, there were tens of thousands of cases of rape of Japanese and Chinese women by the Red Army in Manchuria.
Dismantling of equipment. PHOTO: https://warfarehistorynetwork.com/
For the third time in one decade, Stalin won the conflict with Japan. And for the third time, the victory was achieved because Japan was simultaneously involved in another conflict. As Japan suffered a crushing defeat in World War II, the USSR managed to regain everything that Japan had managed to seize since the mid-nineteenth century. Some sources indicate that Stalin was dissatisfied with the consequences of the conflict. This is hardly true. For several years, the Allies had been asking Stalin to enter into a conflict with Japan, so it appeared as if the USSR had met them halfway. At the same time, the territorial gains were made quickly and with little blood. Of course, the achievements could have been greater. Or they might not have happened at all if the Japanese had laid down their arms after the nuclear strikes.
Researchers continue to debate how great the Soviet contribution to the rapid end of World War II was. The fact is that Japan was ready to continue the fight before the use of nuclear weapons. Moreover, after the first nuclear strike, the Japanese did not stop. However, after August 9, when the USSR attacked and the second nuclear strike took place, Japan quickly asked for peace. In my opinion, Japan was brought down by this double blow, so these events cannot be separated. The Japanese were counting on diplomatic assistance from the USSR, so the violation of the Neutrality Act was a strong blow. On the other hand, the second nuclear strike showed that the United States is capable of doing such terrible things on a regular basis. Moreover, it is now known that the Americans were indeed prepared to do so until Japan laid down its weapons. If you look at the situation from this perspective, the USSR's assistance actually looks superfluous.
Why did the glorious Kwantung Army, which consisted of 700,000 to 1 million soldiers, collapse so quickly under the pressure of Soviet troops? The answer lies in a number of reasons. First, experienced veterans were quickly replaced by newcomers. Second, the USSR had a significant quantitative and qualitative technical advantage. Thirdly, the Japanese in 1945 were demoralized to the maximum extent possible due to constant defeats, fatigue from a long and unpromising war, and nuclear strikes. Obviously, a similar clash in 1942 would have been very different.
The USSR once again proved that it is possible and even worthwhile to violate international treaties if there is nothing to gain from doing so. Ukraine has already faced this, so we should remember that parties fulfill an international treaty if it is beneficial to them or if they are forced to do so.
Олег Пархітько