What was the official document signed by Japan on September 2, 1945, to end the war?

The official document signed by Japan on September 2, 1945, was the Instrument of Surrender. It recorded Japan’s acceptance of the Potsdam Declaration and formally ended hostilities with the Allied powers.

The document stated that Japan accepted the provisions of the declaration and ordered Japanese forces everywhere to cease active operations. It also required Japanese commanders to surrender and prisoners of war to be released and protected.

Two copies were signed aboard USS Missouri in Tokyo Bay. Mamoru Shigemitsu signed for the Japanese government, Yoshijirō Umezu for the armed forces, and Douglas MacArthur signed for the Allied powers. Representatives of other Allied countries added their signatures.

The Instrument of Surrender was not the later peace treaty. The San Francisco Peace Treaty, signed in 1951 and effective in 1952, formally restored Japan’s sovereignty after the occupation. The 1945 instrument instead established the immediate military surrender and occupation arrangements.