The Soviet-Japanese War of 1945 (, lit. Soviet-Japanese War), began on August 9, 1945, with the Soviet invasion of the Japanese puppet state of Manchukuo. The Soviets terminated Japanese control of Manchukuo, Mengjiang (inner Mongolia), northern Korea, southern Sakhalin, and the Kuril Islands. The rapid defeat of Japan's Kwantung Army was a significant factor in the Japanese surrender and the termination of World War II.