The Forgotten Soviet-Japanese War of 1939

Recent Features

Features | Security | Society

The Forgotten Soviet-Japanese War of 1939

From May to September 1939, the USSR and Japan fought an undeclared war involving over 100,000 troops. It may have altered world history.

In the summer of 1939, Soviet and Japanese armies clashed on the Manchurian-Mongolian frontier in a little-known conflict with far-reaching consequences. No mere border clash, this undeclared war raged from May to September 1939 embroiling over 100,000 troops and 1,000 tanks and aircraft. Some 30,000-50,000 men were killed and wounded. In the climactic battle, August 20-31, 1939, the Japanese were crushed. This coincided precisely with the conclusion of the German-Soviet Nonaggression Pact (August 23, 1939) – the green light for Hitler’s invasion of Poland and the outbreak of World War II one week later. These events are connected. This conflict also influenced key decisions in Tokyo and Moscow in 1941 that shaped the conduct and ultimately the outcome of the war.

This conflict (called the Nomonhan Incident by Japanese, the Battle of Khalkhin Gol by Russians) was provoked by a notorious Japanese officer named TSUJI Masanobu, ring-leader of a clique in Japan’s Kwantung Army, which occupied Manchuria. On the other side, Georgy Zhukov, who would later lead the Red Army to victory over Nazi Germany, commanded the Soviet forces. In the first large clash in May 1939, a Japanese punitive attack failed and Soviet/Mongolian forces wiped out a 200-man Japanese unit. Infuriated, Kwantung Army escalated the fighting through June and July, launching a large bombing attack deep inside Mongolian territory and attacking across the border in division strength. As successive Japanese assaults were repulsed by the Red Army, the Japanese continually upped the ante, believing they could force Moscow to back down. Stalin, however, outmaneuvered the Japanese and stunned them with a simultaneous military and diplomatic counter strike.

In August, as Stalin secretly angled for an alliance with Hitler, Zhukov amassed powerful forces near the front. When German Foreign Minister Ribbentrop flew to Moscow to sign the Nazi-Soviet Pact, Stalin unleashed Zhukov. The future Red Army Marshal unveiled the tactics he would later employ with such devastating effect at Stalingrad, Kursk, and elsewhere: a combined arms assault with massed infantry and artillery that fixed the enemy on the central front while powerful armored formations enveloped the enemy’s flanks, encircled, and ultimately crushed him in a battle of annihilation. Over 75 percent of Japan’s ground forces at the front were killed in combat. At the same time, Stalin concluded the pact with Hitler, Japan’s nominal ally, leaving Tokyo diplomatically isolated and militarily humiliated.

The fact that the fighting at Nomonhan coincided with the German-Soviet Non-Aggression Pact was no coincidence. While Stalin was openly negotiating with Britain and France for a purported anti-fascist alliance, and secretly negotiating with Hitler for their eventual alliance, he was being attacked by German’s ally and anti-Comintern partner, Japan. By the summer of 1939, it was clear that Europe was sliding toward war. Hitler was determined to move east, against Poland. Stalin’s nightmare, to be avoided at all costs, was a two-front war against Germany and Japan. His ideal outcome would be for the fascist/militarist capitalists (Germany, Italy, and Japan) to fight the bourgeois/democratic capitalists (Britain, France, and perhaps the United States), leaving the Soviet Union on the sidelines, the arbiter of Europe after the capitalists had exhausted themselves. The Nazi-Soviet Pact was Stalin’s attempt to achieve his optimal outcome. Not only did it pit Germany against Britain and France and leave the Soviet Union out of the fight – it gave Stalin the freedom to deal decisively with an isolated Japan, which he did at Nomonhan. This is not merely a hypothesis. The linkage between Nomonhan and the Nazi-Soviet Pact is clear even in the German diplomatic documents published in Washington and London in 1948. Recently revealed Soviet-era documents add confirming details.

Zhukov won his spurs at Nomonhan/Khalkhin Gol – and thereby won Stalin’s confidence to entrust him with the high command in late 1941, just in time to avert disaster. Zhukov was able to halt the German onslaught and turn the tide at the gates of Moscow in early December 1941 (arguably the most decisive week of the Second World War) in part by deploying forces from the Soviet Far East. Many of these were the battle-tested troops he used to crush the Japanese at Nomonhan. The Soviet Far Eastern reserves – 15 infantry divisions, 3 cavalry divisions, 1,700 tanks, and 1.500 aircraft – were deployed westward in the autumn of 1941 when Moscow learned that Japan would not attack the Soviet Far East, because it had made an irrevocable decision for southward expansion that would lead to war with the United States.

The story of Japan’s road to Pearl Harbor is well-known. A part of that story that is not so well-known is that memories of their defeat at Nomonhan figured in Japan’s decision for war with the United States. And the same Tsuji who played a central role at Nomonhan was also an influential advocate for southward expansion and war with America.

In June 1941, Germany invaded Russia and in the early months of the war inflicted such crushing defeats on the Red Army, many believed the Soviet Union was on the verge of collapse. Germany urged Japan to invade the Soviet Far East, avenge the defeat at Nomonhan, and seize as much Soviet territory as it could swallow. But in July 1941, the United States and Britain had imposed an oil embargo on Japan that threatened to starve the Japanese war machine. To avert this, the Imperial Navy was determined to seize the oil-rich Dutch East Indies. The Netherlands had been conquered a year earlier. Britain was fighting for its life. Only the U.S. Pacific Fleet stood in the way. Many in the Japanese Army, however, were keen to attack the U.S.S.R., as Germany was urging. They wanted to avenge the defeat at Nomonhan while the Red Army was being smashed by the blitzkrieg. Japanese Army and Navy leaders debated this issue at a series of Imperial War Conferences.

In the summer of 1941, Col. Tsuji was a senior operations staff officer at Imperial General Headquarters. Tsuji, a charismatic and forceful spokesman, was one of the Army men who backed the Navy position that led to Pearl Harbor. General Tanaka Ryukichi, Chief of the Army Ministry’s Military Service Bureau in 1941, testified after the war that, “… the most determined single protagonist in favor of war with the United States [was] Tsuji Masanobu.” Tsuji later wrote that his experience of Soviet fire-power at Nomonhan convinced him not to take on the Russians in 1941.

But what if there had been no Nomonhan Incident, or if it had ended differently, say in a stalemate or a Japanese victory? In that case, the Japanese decision to move south might have turned out very differently. A Japan less impressed with Soviet military capability and faced with choosing between war against the Anglo-American powers or joining Germany in finishing off the U.S.S.R., might have viewed the northern course as the best choice.

If Japan had decided to attack northward in 1941, that could well have changed the course of the war, and of history. Many believe that the Soviet Union could not have survived a two-front war in 1941-1942. The Soviet margin of victory in the Battle of Moscow, and at Stalingrad a year later, was excruciatingly thin. A determined Japanese foe in the east might have tipped the balance in Hitler’s favor. Furthermore, if Japan had moved against the Soviet Union in 1941, it could not also have attacked the United States that year. The United States might not have entered the war until a year later, under circumstances in Europe far more unfavorable than the actual grim reality in the winter of 1941. How then would Nazi domination of Europe been broken?

Nomonhan cast a long shadow.

Stuart D. Goldman is a Russian specialist and a scholar in residence at the National Council for Eurasian and East European Research. This article is based on his book, NOMONHAN, 1939: The Red Army’s Victory That Shaped World War II (U.S. Naval Institute Press).