also known as the "Soviet-Japanese Border War" or the first “Soviet-Japanese War”, was a series of minor and major conflicts fought between the Soviet Union and the Empire of Japan from 1932 to 1939. Japan's expansion into Northeast China created a common border between Japanese controlled areas and the Soviet Far East and Mongolia. The Soviets and Japanese, including their respective client states of the Mongolian People's Republic and Manchukuo, disputed the boundaries and accused the other side of border violations. This resulted in a series of escalating border skirmishes and punitive expeditions, including the 1938 Battle of Lake Khasan, and culminated in the Red Army finally achieving a Soviet-Mongolian victory over Japan and Manchukuo at the Battle of Khalkhin Gol in September 1939. The Soviet Union and Japan agreed to a cease-fire. Later the two sides signed the Soviet–Japanese Neutrality Pact on 13 April 1941, which resolved the dispute and returned the borders to status quo ante bellum. Winter War with Finland The Winter War (, , ) was a war between the Soviet Union and Finland. It began with a Soviet offensive on 30 November 1939—three months after the start of World War II and the Soviet invasion of Poland. The League of Nations deemed the attack illegal and expelled the Soviet Union on 14 December 1939. The Soviet forces led by Semyon Timoshenko had three times as many soldiers as the Finns, thirty times as many aircraft, and a hundred times as many tanks. The Red Army, however, had been hindered by Soviet leader Joseph Stalin's Great Purge of 1937, reducing the army's morale and efficiency shortly before the outbreak of the fighting. With over 30,000 of its army officers executed or imprisoned, most of whom were from the highest ranks, the Red Army in 1939 had many inexperienced senior officers. Because of these factors, and high commitment and morale in the Finnish forces, Finland was able to resist the Soviet invasion for much longer than the Soviets expected. Finnish forces inflicted stunning losses on the Red Army for the first three months of the war while suffering very few losses themselves. Hostilities ceased in March 1940 with the signing of the Moscow Peace Treaty. Finland ceded 9% of its pre-war territory and 30% of its economic assets to the Soviet Union. Soviet losses on the front were heavy, and the country's international reputation suffered. The Soviet