What was the Soviet operation that began the invasion of Japanese-held Manchuria in August 1945?

Operation August Storm was the Soviet operation that began the invasion of Japanese-held Manchuria in August 1945. The Soviet offensive started on August 9, 1945, against Japan’s Kwantung Army.

Soviet forces attacked across a vast front from the Soviet Far East, Mongolia, and areas near the Chinese border. The operation rapidly overwhelmed Japanese defenses and also targeted Japanese positions in northern Korea, southern Sakhalin, and the Kuril Islands.

The invasion was one of several major developments confronting Japan during the final week of the war. It followed the atomic bombing of Hiroshima and occurred on the same day as the bombing of Nagasaki, although the Soviet declaration of war had been delivered shortly before the offensive began.

Historians debate the relative weight of the atomic bombings and the Soviet attack in Japan’s decision to surrender. The invasion nevertheless destroyed Japan’s strategic position in northeast Asia and influenced postwar borders and occupations.