In 1939, both Hitler and Stalin feared fighting a two-front war. Hitler wanted to focus on conquering Western Europe without having to worry about his eastern flank. Stalin had no interest in being embroiled in a two-front war. Japan had been harassing the Soviet Union’s eastern flank for almost a decade. The Soviet Union also wanted to add territory in Eastern Europe without upsetting Germany. While Soviet foreign minister Vyacheslav Molotov and German foreign minister Joachim von Ribbentrop negotiated a Pact that would lead directly to the outbreak of WWII, a little known battle near Manchuria would influence German-Soviet negotiations and shape the fighting of WWII.
Great Britain competed with Germany for the Soviet Union’s hand in an alliance during the summer of 1939. The British wanted the Soviet Union to check German aggression. Though Britain had a stronger navy than Germany, Britain was still at a disadvantage in securing a Soviet alliance. The Soviet Union would still have to fear a two-front war with a British alliance.
The Soviet Union had been on the defensive on their eastern front ever since the Japanese occupied Manchuria in 1931. Japan repeatedly tested Soviet strength and will in outer Mongolia (present-day Mongolia). Japan dreamed of a Greater East Asian coalition that included a united Mongolia. Japan wanted Russian protected outer Mongolia, Japanese-controlled inner Mongolia, and some northern Chinese provinces to form one Mongolian nation. The Soviet Union feared a strong, unified Mongolia on their eastern border. So the Soviet Union sought to keep the Mongols divided and isolated. These opposing visions for the Mongols fueled Soviet desires to secure their western flank. War on their eastern flank seemed inevitable.
Outer Mongolia (the Mongolian People’s Republic) and the Soviet Union verbally agreed that the Soviets would defend the Mongolian People’s Republic (MPR) against outside aggression. This agreement, aimed at Japan, was formalized in March 1936. A lull in the war between Communist Chinese forces and invading Japanese forces delivered Japan an opportunity to test the Soviet Union more aggressively.
Japan began testing the MPR’s border in December 1938. The contested sector formed a rectangle 50 miles long and up to 20 miles wide along the Khalkha River. Japan sent small patrols to skirmish with Mongol border patrols and then retreat. Japan did this repeatedly until May 28, 1939. Japan interpreted limited Soviet counterattacks as weakness.
A 4,500-strong Japanese force attempted to encircle a 1,500-man Mongol/Soviet force on May 28th, five miles east of the Khalkha river. Timely Soviet reinforcements turned this encirclement attack back. The battles became almost solely between Japanese and Soviet forces. Both tested their latest fighter planes that clashed in numerous air battles and dog fights. July saw Japan increase their forces to 25,000 troops and bring in hundreds of modern weapons whether machine guns, artillery, anti-tank guns, and tanks. But … Japan would not have enough of the right kind of modern weapon.
Only 12,000 Soviets and 500 Mongols stood battle-ready. Japan struck their positions at several points in early July in Japan’s largest offensive. General Georgyl Zukhov, commander of Soviet-Mongol forces, used his armada of over 450 tanks and armored vehicles, as well as air support to great effect. Zukhov managed to encircle and destroy Japanese troops that had driven into Mongol territory. Japan with insufficient armor to oppose this encirclement lost 4,000 men according to Soviet estimates. The initiative swung back to the Soviets from July 6th until August 20. Artillery and air strikes dominated this phase as Japan tried constructing more defensive fortifications. Japan sent reinforcements mainly from China to bring their troop total to around 100,000. The Soviets also reinforced the war zone. Soviets attempted an armored double flanking encirclement for maybe the first time in military history. The Soviets successfully encircled the Japanese army again between August 20th and August 31st. The Japanese lost around 55,000 men, 25,000 of them killed, in their ultimate defeat.
Japan admitted to losing 18,000 casualties, its highest admitted casualty number from 1931 until the end of WWII. The Soviet Union successfully demonstrated their latest strategy based on battling for air superiority at the beginning with major ground forces being brought in to puncture and encircle the enemy. The Battle of Nomonhan-Khalkin Gol was the “first test of Soviet strategy since the Russian Civil War.”
While this series of battles turned against Japan, the Soviet-German Non-Aggression Pact was signed on August 24, 1839. News of this Pact stunned the Japanese. A “complete turn-about of Japanese policy” resulted. Japan had been focusing on growing its military-industrial capacity by trying to dominating resource-rich areas in Korea and Manchuria. This drive brought them into conflict with a weaker China, but ultimately a Soviet Union that proved surprisingly strong. After the Soviet-German Non-Aggression Pact and after the Battle of Nomonhan-Khalkin Gol, Japan turned towards what she believed to be softer targets in nearby British and American colonies in Southeast Asia and beyond.
The Soviet-German Non-Aggression Pact produced a ripple effect that shook Europe. The grand clash of modern militaries at Khalkin Gol produced waves that would be felt globally. Some waves crashed immediately. Others didn’t for years. Hitler invaded western Poland on September 1st, just a week after the Pact was signed. Stalin invaded eastern Poland on September 17, less than three weeks after defeating the Japanese at Khalkin Gol. These two thrusts are common knowledge to many WWII history buffs.
The Battle of Nomonhan-Khalkin Gol’s link to the Battle of Stalingrad is not common knowledge. Operation Barbarossa dashed Stalin’s hope of pacifying Germany less than two years after the Soviet-German Non-Aggression Pact’s signing. In 1939, Stalin had laid fertile ground for a German invasion when he purged more than 60% of his military commanders at all levels for fear they weren’t loyal enough to him. He executed about 90% of his highest commanders. Inexperienced, poorly led Soviet forces were annihilated during the early weeks of the German invasion in the summer of 1941.
This is where Khalkin Gol came in. Stalin had 1,700 tanks and 18 army divisions and 1,500 aircraft shifted from Mongolia to help stop the German advance. Some historians credit these battle-tested troops and equipment with decisively turning the tide of the German invasion. Soviet tanks proved more than a match against German panzers. Partly because of his family’s lower-class status, General Zukhov (leader of Soviet-Mongol forces previously) survived Stalin’s purges. Zukhov’s experience proved crucial in the Battle of Stalingrad that decisively bled the vast majority German army into eventual surrender.
The Battle of Nomonhan-Khalkin Gol also determined the fate of Mongols for decades. The Japanese defeat spelled a split between Inner Mongolia and Outer Mongolia. A Mongol union that Japan and some Mongol nationalists had hoped for was further thwarted by WWII. Inner Mongolia was eventually absorbed by China with those Mongols having autonomy only in name. The MPR’s “freedom” depended on the Soviet Union for decades until the USSR’s dissolution.
More can be found in the following sources:
Lecture 33 of The Decisive Battles of World History available on Great Courses Plus.
MOSES, LARRY W. “SOVIET-JAPANESE CONFRONTATION IN OUTER MONGOLIA: THE BATTLE OF NOMONHAN-KHALKIN GOL.” Journal of Asian History 1, no. 1 (1967): 64-85. Accessed June 27, 2020. www.jstor.org/stable/41929840.