One of the most decisive battles of World War II
was in a place called Khalkhin Gol (or Nomonhan), Mongolia
, between the Empire of Japan
and the Soviet Union
. This was the largest of several border skirmishes between Russian and Japanese forces, and directly impacted the war back in Europe
's Eastern Front
In 1939, the Russian Army had about forty divisions (almost all light infantry) on the border with Japan. Japan thought that the twelve or so divisions it had in the area would be more than a match for the Russians, mostly based on experiences in the previous Russo-Japanese War (1904-05). In May, 1939, Japan marched a division to the Khalkhin Gol (or Halha) River, but was turned back by a reinforced Russian division.
In July of 1939, Japan again attacked Khalkhin Gol, this time with an extra infantry regiment, and seventy tanks. Japanese leadership thought that since the battle area was some five hundred miles from the nearest rail line, the Russians would be unable to properly supply their forces against a sustained assault. Japan again marched on Khalkhin Gol.
Unfortunately for Japan, Russia had just sent their General Georgi Zhukov (who went on to be one of the star Russian generals on the Eastern Front), and he had brought three-hundred tanks with him. Japan's July 3 offensive made some progress, but was again beaten back, and by July 14, the fighting ground to a halt with Japan's retreat.
Japan's new plan was to use artillery to decimate the Russians. The two sides dueled for a week, but the Russians ended up being able to fire three times as many shells farther (and heavier ones too) than the Japanese. Japan was again defeated.
August of 1939 saw Russia go on the offensive. General Zhukov launched an attack using four full infantry divisions, and five hundred tanks. This was the first real armored offensive of World War II, since Germany's Blitzkrieg invasion of Poland and France had not yet occurred. Japan went up against Russia's forces with only two divisons, and Japan was crushed, being pushed back all the way to the original border. Zhukov could have pursued the Japanese forces further, but didn't. Later, the Soviet Union and Japan signed a cease fire.
This had a massive impact on the rest of the war. With the cease fire signed, the Soviet Union was free to move the forty divisions it had on the border with Japan to the Eastern Front to fight Germany. They arrived just in time to beat back the Germans advancing on Moscow, and pursued the German army all the way back to Berlin. If the battle of Khalkhin Gol had not been fought, then there would have not likely been a Russo-Japanese cease fire, meaning that the forty divisons on the border would have remained tied up. Without the forty divisions on the Eastern Front, the Soviet Union may have been brought to its knees by Germany.
Furthermore, neither Japan nor the Soviet Union let much information about the battle out. If Germany had known of Japan's failure to invade Russia (something they were apparently counting on to tie up Russian forces in the Far East), then that may have made Hitler's Russian Adventure significantly less appealing.
Yet another of the many What Ifs of World War II.