On what date did the Soviet Union begin invading Japanese-held Manchuria in 1945?

The Soviet Union began invading Japanese-held Manchuria on 9 August 1945.

The Red Army launched the Manchurian Strategic Offensive Operation against Japan’s puppet state of Manchukuo and related Japanese-held territories. Soviet forces attacked from several directions, overwhelming the Kwantung Army in a rapid campaign across Manchuria, Inner Mongolia, and northern Korea.

The invasion began between the atomic bombings of Hiroshima on 6 August and Nagasaki on 9 August. Japan’s leaders had hoped the Soviet Union might mediate with the Western Allies, so the Soviet declaration of war destroyed an important diplomatic possibility.

Historians continue to debate how much the Soviet attack, the atomic bombings, and the broader military situation each influenced Japan’s surrender. The Kwantung Army formally surrendered on 16 August, although fighting in parts of Asia continued until the formal surrender ceremony on 2 September.