All through the late 1940’s North Korean leader Kim Il Sung pushed on Stalin, the leader of the Soviet Union, to sanction and support an invasion of South Korea. With the victory of the Communists on the Chinese civil war in 1949 and continued pressure from Kim, Stalin agreed to April 1950. The north invade South Korea on June 25, 1950 and in a matter of days had overrun the South Korean forces and the few American forces and pushed past Seoul far into the south. The U.N. placed all forces under the command of General Douglas MacArthur, who realized only American ground forces could turn the tide. The problem: The U.S. Army, which was 8,000,000 strong in 1945 was now only at 500,000 and the Marine Corps down to 75,000. With the beleaguered South Korean and American forces pushed south to Pusan in the southeast corner of the peninsula, American troops began to arrive from the Army divisions stationed in Japan to reinforce this last bastion: The Pusan Perimeter.