99: Changkufeng


During 1938 the border tensions between the Soviet Union and Japan would explode on the hill of Changkufeng near Lake Khasan.


  • Anti-Russian and Anti-Soviet Subversion: The Caucasian-Japanese Nexus, 1904-1945 by Hiroaki Kuromiya and Georges Mamoulia
  • Japanese Geopolitics and the Mongol Lands, 1915-1945 by Li Narangoa
  • Khalkin-Gol: The Forgotten War by Amnon Sella
  • The Lake Khasan Affair of 1938: Overview and Lessons by Alvin D. Coox (1973)
  • Soviet-Japanese Confrontation in Outer Mongolia: The Battle of Nomonhan-Khalkin Gol by Larry W. Moses (1967)
  • Nomonhan: Japan Against Russia, 1939 by Alvin D. Coox
  • Nomonhan, 1939: The Red Army’s Victory That Shaped World War II by Stuart D. Goldman


Hello everyone and welcome to History of the Second World War Episode 99 - Nomonhan Pt. 1 - Changkufeng. This week a big thank you goes out to Eric for the donation and to Craig, Gretchen, Jeffrey, James, Piping, Frederick, Maxine, and Julie for choosing to become Members so that they get ad free versions of the podcast plus special member only episodes once a month. If that sounds interesting to you head on over to historyofthesecondworldwar.com/members to find out more. I would also like to apologize to all of the wonderful people who have supported by using Apple Podcast Subscriptions, in a move I have a hard time disagreeing with, Apple does not provide me with any information about you, so no name shoutouts for Apple Subscribers, but know that I thank you. After focusing on European affairs for basically the entirety of this season of the podcast, we are now going to shift back to the East to discuss the fighting that would occur during the summer months of 1938. Then over the three episodes after this one we will discuss what the Japanese could call the Nomonhan Incident and the Soviets would refer to as the Battle of Khalkin Gol. I probably will not lead episodes with a conversation of names given to battles by both sides, as it is very frequent that the two sides would refer to events by different names, but for this battle it ties into a wider conversation about the historiography of the events that will be covered over the next four episodes. As with much of the fighting that would occur in Asia in the years before 1941, when reading about these events in English the numbers of sources is not exactly overwhelming. They are out there, there are things to read, but many of them are at this point quite dated. That is important in this case because everything written before 1990 very clearly is based very heavily on Japanese sources, with only official Soviet accounts taken into consideration, and this can present a real challenge for wider understanding of the events due to how heavily most English writing is based strictly on Japanese participants, government, and army sources. These are more recent books written about the fighting that are a bit more all inclusive, with Nomonhan, 1939 by Stuwart Goldman probably being the best option, but if you wanted out into the wide world of the internet you will almost certainly stumble upon older sources as well. A good way to identify the sources used for the work is to see how it refers to Soviet troop and equipment numbers, if it is based only on Japanese sources, or is pulling from secondary sources built on top of Japanese sources you will end up seeing things like “the Japanese estimated the Soviets had 100 tanks” or “the Japanese intelligence reports were that the Soviets had 3 divisions.” I bring this subject up partially because you will hear me say things like that in this podcast, I did my best to sort through the information available, but you will be hearing far more about the actions and decisions of the Japanese in these episodes than the Soviets, and you will also hear me sometimes use Japanese estimates of Soviet numbers, which I will try to very clearly call out. So with that disclaimer out of the way, let’s talk about why the Soviet Japanese border regions were filled with conflict in the last years of the 1930s.

Way back in Episodes 50 through 56 we discussed the beginning of Japan’s expansion on the Asian mainland, starting with the expansion of their area of control in Manchuria, from which they would also begin to expand to the south. At the same time that they were attempting this move south they were also expanding their control to the West and into Mongolia, where they hoped they would be able to end their expansion after obtaining two important benefits. The first was that it would prevent the Soviet Union from expanding their influence into the area, into what was an area between two large empires. The second was that it could provide a buffer zone that would keep any Soviet aggression away from Korea and Manchuria, both of which were growing more and more economically essential for the Japanese war effort. For those keeping track, this had also been the reason that the Japanese had expanded into Manchuria and created Manchukuo, to expand its borders and create a buffer zone to protect Korea. Instead of solving the problem, this expansion simply moved the border north and west and created the same set of problems once again. During these efforts the Japanese tried to utilize the same tactics that they were also using in northern China, working to bring local leaders into collusion with Japan as the first step to fully asserting Japanese control of the area, in this case that area being Outer Mongolia. While expanding the territory under Japanese control was one of the goals of the actions being taken at this stage, all of these actions were also driven by fear of the threat posed by the Soviet Union, which would drive many actions of the Imperial Japanese Army during the 1930s. The Soviets were the enemy that all Japanese Army planning was based around, with this fear continually increased by the efforts of the Soviet Union to further build its industrial base during the First and Second Five Year Plans. There was even one theory that the Soviets would adopt a very aggressive policy in Eastern Asia by the mid-1930s, and this prompted real discussions of a preventative war by the Japanese Army in the years after 1932. The Japanese assumptions of Soviet intentions would prove to be incorrect, but the Japanese fear of Soviet strength in the years that followed was absolutely valid, as shown by what would happen during the Second World War. While recognizing the economic and demographic advantages that the Soviet Union would possess in the future, there was also the belief that regardless of numbers the Japanese military would always be superior in what were felt to be some key aspects. These mostly revolved around what I would call qualitative metrics: training, discipline, morale, and bravery. The unshakeable belief in the superiority of the Japanese soldiers did not prevent some misgivings among Japanese army leadership, who were concerned about the overall military strength of the Soviet Union. By 1938 there were concerns that if the Japanese had a window to attack the Soviet Union it might either be closing, or had even already closed. But there was in no way widespread agreement about the relative balance of power at any given moment. There were most importantly very serious disagreements between the leaders in Japan at Army headquarters and those that commanded the armies in the area, particularly among the leadership of the Kwantung Army based in Manchukuo. The Kwantung Army was one of the most powerful formations in the Japanese Army, and would remain so even as the war expanded in China due to fears that the Soviets could take advantage of the war in China to launch their own attack. The Kwantung Army would have a constantly updated plan for a war with the Soviet Union, which generally involved the Kwantung Army holding a defensive line in most of Manchuria while Japanese offensive efforts were focused on the Maritime Province of the Soviet Union was was positioned to the east of the Japanese held territories, sandwiched between Manchukuo and the Pacific Ocean. Because of its importance in these plans the Kwantung leadership possessed a lot of power, and they used that to their advantage, as it would be the Kwantung Army leadership that would push for expanding as much as possible out of Manchuria and into Outer Mongolia, with the justification being that it was the only way to stamp to Chinese resistance movements in Manchukuo.

During the last half of the 1930s this urge to expand Japanese control result in a series of border confrontations between Soviet and Japanese forces around the border region between both sides. Some of these did not result in a lot of fighting, while others would flair up into short confrontations. They would continue to increase in intensity each year after 1937, with the two that would occur in 1938 and 1939 reaching new levels of violence. The reason that this kept happening was down to the fact that the exact position of the border between Japanese controlled or influenced areas and Soviet controlled or influenced areas was disputed. Both groups felt that they actually were entitled to more territory than what the other side believed, and there were also not enough troops stationed in the region to consistently man any kind of front. This happened along most of the border areas, both in Mongolia where the power and control situation was very fluid, and in the Maritime Province near the Pacific coast, where the control of the area was less confused, but there were still several areas under dispute. In the Maritime Province the border had technically been settled in 1886, when a treaty had been signed to finalize the borders between Manchuria, Russia, and Korea but even within that agreement there were differences between the Russian and Chinese texts, with the Japanese using the latter. This disputed territory would result in the 1938 clash which was called the Changkufeng Incident by Japan, where there would be fighting in July and August. It would begin when the Kwantung army intelligence group intercepted a message in early July which was sent to the Soviet commander in the area. This message gave orders for the Soviets to occupy some high ground to the west of Lake Khasan, part of that high ground was Changkufeng Hill. This was about 60 miles southwest of Vladivostok and is today right along the area where the borders of Russia, North Korea, and China meet. In 1938 this was disputed territory and so the Japanese felt that the actions being taken by the Soviets infringed upon their own territory. There was also a concern because the hill provided advantages for either side if they were able to control it due to its ability to command the surrounding areas for several miles. This included the ability to put artillery on the hill to shell the local railway. The area was not actually within the Kwantung Army’s area of responsibility and was instead defended by the Korean Army, but given the Kwantung Army’s level of influence it was able to play a role in forcing action. Back in Tokyo there was resistance to doing anything that would cause fighting with the Soviets, with their concern being events in China that were continuing to pull more and more troops to the south to deal with the ever escalating fighting, the Battle of Shanghai had ended just six months earlier, and the territory under Japanese control was continuing to expand. These events results in troops being moved south to reinforce units in China, which resulted in the Kwantung and Korean Armies having just 7 infantry divisions between them. While discussions about how to respond were still occurring on the Japanese side, the Soviet forces that had advanced onto the hill would spend several days building defenses. On July 16th orders would be sent out to the 19th division to begin moving towards the Tumen River, which ran along the border region just a bit west of Lake Khasan and Changkufeng. The 19th division was under the command of General Suetaka, who was under explicit orders to not take any actions in the area under he was provided with specific orders to do so. On July 19th the first Japanese troops would be arrive at the river. While they were being positioned, in Moscow the Japanese would formally request that the Soviets withdraw from the area, a request that was denied with the excuse that the Soviet government considered it Soviet territory so the Red Army could put troops there whenever it wanted to. With the easy path no longer possible, Kwantung army leadership began to badger Tokyo with requests and demands that they be allowed to launch an attack to push the Soviets off the hill by force. While the primary origin of calls for actions were from the armies in the area, there were also those within Imperial Headquarters, especially younger lower ranked officers, that also strongly believed that the Japanese had to use force in the current situation. This included Colonel Inada Masazumi, who held the position of Chief of the Operations Section of the Imperial Army. Inada saw the Soviet actions as an opportunity for the Japanese Army to test both the capabilities of the Red Army and its intentions in the area. On July 19th, the plan to launch an attack was finally approved by Army leadership, and also passed through the Japanese Cabinet in a close vote. This new plan was forwarded to the Korean Army headquarters, with the 19th division to attack and take Changkufeng, but it was very clearly stated that they should advantage no further beyond the hill. If the Soviets counterattacked the Japanese forces would of course resist and continue to hold the hill, but that was all they could do. The most important aspect of these restrictions was that the Japanese forces were not to expanded the scope of the confrontation in any way, to the point where they were not even allowed to use aircraft in the attack due to concerns that this would result in escalation. There was just one problem with these orders, they did not yet have Imperial consent, which was an essential element in all Japanese military plans. The Emperor seems to have been concerned about the consequences of more fighting with Soviet forces and was less convinced that it was necessary. This was communicated to the front on July 20th, with Inada including in the message “We have not been able to obtain imperial sanction for the order authorizing use of force…be prudent in your guidance so as not to provoke incidents.” And so, nothing happened, with the forces of the 19th division slowly reducing their presence on the eastern side of the river over the following days.


On July 29th, it would be the actions of the Soviet Union that would ignite the fighting in the area of Changkufeng when some Soviet troops were spotted on another hill to the north of their previous positions. They were generally emboldened by the fact that they could see that most of the Japanese forces that had concentrated in the area had left the area before the 29th, and so they felt they could expand their area of control. The hill in question was Shachaofeng Hill, which was about 2 kilometers north of Changkufeng and was felt to be firmly in Japanese territory, and so instead of waiting on orders the commanders on the scene ordered and assault on their own initiative. This resulted in over 100 Japanese soldiers being thrown into an attack against just 10 Soviet border guards. All of the Soviet soldiers were either killed or wounded, and the Japanese attack would be answered very quickly when just a few hours later more Soviet forces from Changkufeng, two companies of the 119th Infantry regiment, launched a counter attack. They were also accompanied by several tanks, which were very useful when the attack was launched at 5PM which pushed the Japanese back off of the hill. After the attack and counterattack General Suetaka saw his opportunity, and he would order troops of the 19th division to attack the next day. He would also make another decision, and he told all of his officers not to report on his plans to Headquarters in Tokyo, under the reasoning that they might order them to be cancelled. This concern was due to the fact that Suetaka was not just aiming to take back the new hotspot of Shachaofeng, but also to launch the previously planned attack on Changkufeng as well. To do this he would dispatch the 75th Infantry Regiment under Colonel Sato Kotoku, who would launch the attack at night with one company attacking Shachaofeng while the rest of the 75h Regiment was focused on Changkufeng. This attack was scheduled for the early hours of July 31st, to give the attacking forces the greatest opportunity to maintain the element of surprise before they launched their attack. And in fact the Soviet defenders would not discover that the 75th Regiment had crossed the river under the attack was launched and they were engaged in combat. The assault on the hill would be launched by 1,600 men, who made up the best troops that Colonel Sato had under his command. They would begin their crossing of the river just after 2AM, with the assault to immediately follow. By just a little after 5AM they already controlled the top of the hill, with the final Soviet defenders retreating at 6AM. The Japanese would suffer under 50 killed and around 100 wounded, numbers are a bit fuzzy there, the Soviet forces would claim that they had 13 killed and 55 wounded, as well as one tank and artillery piece destroyed. The Soviet numbers area also a bit suspect, which will be a theme throughout all of these events as there is the general belief that the official Soviet figures are not completely accurate. Even if they had suffered some losses, the overall result of the attack was one of great success, but the finding was not yet over.

Moscow learned of the events of that had occurred in the early morning hours of July 30th and they would make the decision to meet force with force, with more units dispatched into the area. Marshal Voroshilov, chief of staff of the Red Army would send a message on August 1 that the local Red Army forces were to “Destroy those who have intruded within the limits of our boundaries.” The Soviet attacks would be launched by troops of the 39th Corps commanded by General Grigori Shtern, and unlike the Japanese forces there would be few restrictions on how the operation could unfold. Most importantly this meant that the Red Air Force would be used to its greatest ability, with the air raids being launched starting on August 1st and continuing until fighting ended. They focussed their efforts on the troops on the hills and then their logistical connections to the rear of their lines. While these air attacks were ongoing, it was going to take time to concentrate the full Soviet forces to launch their attack, with the full concentration not being possible until August 5th. General Shtern was a bit impatient though, and instead of waiting for all of his units to be ready he would begin by sending forward assaults by troops in the area on August 1st when 3,000 men of the 40th division were used in an attack on both hills. These attacks were continued on August 2nd and 3rd as more and more of the 39th corps arrived in the area. The Japanese 75th Regiment would still be in the positions they had taken several days before, and they would perform well in repulsing the continued attacks while under heavy artillery fire. The artillery fire was a real problem, and when it was combined with the constant Soviet air operations General Suetaka would begin to believe that the 19th Division needed to do something other than sit on the hills and be slowly ground down. One idea that was formulated was for a flanking attack to be launched by the 76th Regiment which would attack some surrounding hills, but there was a problem, these hills would be firmly within the Soviet areas of control, and would clearly be a violation of Soviet territory. However, this was almost certainly the correct action from the military perspective, and so it was approved by the Korean Army headquarters, but when it reached Tokyo it was emphatically rejected. And it was not just that plan that was rejected, but also there were specific orders given to the 19th division that it was not to expand the fighting in anyway, either geographically or through the use of air support. They were also told not to retreat from the hills, which kind of just left them with the one option they had been trying to avoid, side on the hills while they slowly got ground down by Soviet attacks. The constraints placed on the defenders would turn events on the hill into a foregone conclusion as the Red Army and Air Force continued to expand the resources they were putting into their attacks. There would eventually be over 100 soviet aircraft and around 200 Russian tanks used in the attacks, while the infantry of the 19th division would be outnumbered as least 2 to 1. The official Japanese account of August 6th would state “Japanese positions appeared to be on the verge of collapse. The defenders managed to hold on, however, with the aid of steadily received reinforcements from the 19th Division.” while on August 7th “Again the Japanese defenses appeared to be crumbling, but the units still clung to the heights.” Additional Japanese artillery was brought into the area in an effort to try and reduce the Soviet firepower advantage, but even pulling guns in from the Kwantung army would prove to be insufficient. As one Japanese soldier would later recount: “Enemy guns would attack us in succession, against targets from our left to our right. Then they would repeat the process again and again. Their aim grew more skillful until we had no dead angles left and no place to hide.” Tanks were also an area where the Japanese had little answer, especially due to the fact that they were ordered not to commit their own armored units. Major Hirabari, who would participate in the fighting would say “We have had to suffer quite a lot from Soviet tanks. They made use of the terrain to come to close quarters and fire at us. The firing was terrific and accurate. Adapting themselves to the terrain, Soviet tanks frequently displayed only their turrets when they wanted to fire. Our fire was not sufficiently effective.". By August 10th the overall situation on the ground was clear, if the Japanese did not do something different, then they would only be able to continue fighting as long as the 19th Division had men remaining, and it would only tkae so long for the 19th to be completely annihilated. On the Soviet side, as the troops they were facing grew weaker, they simply grew stronger, with more men, artillery, and aircraft reaching the front every day. One final problem that the Japanese had was that the troops around Changkufeng had been in action since July 30th when the first assaults were launched, and as casualties mounted it was harder to give the remaining units any kind of reasonable rest.

On August 10th, in Moscow the Japanese would propose a ceasefire and a withdraw of their troops 1 kilometer from their current positions. The Soviets would agree, and a joint border commission would be created to decisively determine the border in the area. The ceasefire would come into effect on August 11th, at which point local commanders would meet to arrange the precise details of how the two armies would disentangle themselves. Shortly after the fighting ended the Japanese would retreat even further back from the hills, moving everything back to the western side of the Tumen river. With the fighting over, the cost of the operations could be tallied. The numbers here are fuzzy, with almost every source I could find saying that the actual numbers were almost certainly higher than what was reported by the armies and by the governments. On the Japanese side the 19th division recorded 526 killed and 914 wounded, while the officially announced number was somewhat lower than that. On the Soviet side a Military council of inquiry would put the number at 408 killed and 2807 wounded, but there is some dispute there, of course the Japanese would claim that the number was much higher, up to twice the official soviet number. In the aftermath of the fighting, and as both sides evaluated their performance there was blame thrown around on both sides for what had happened. Marshal Blyukher, commander of the Trans-Baikal Military District would be accuse of being a Japanese spy and would be executed, but this was at the height of the purges and so there were all kinds of accusations like that being thrown around. General Shtern, even though the attacks he launched had been very costly, would be promoted to take the Marshal’s place. On the Japanese side, the action was seen as a failure, but they did have the opportunity to learn at least a little about Soviet military operations. What would leave a lasting impression was the large amount of material that the Soviets could dedicate to an operation, in the form of aircraft, tanks, and artillery. Over a third of all Japanese casualties had been caused by artillery, something that could have been a valuable lesson, but it would be somewhat ignored in preparation for the next major clash of the two armies. We will begin the story of that clash, which would take place in Mongolia, next episode.