What was the official document signed aboard USS Missouri that recorded Japan’s capitulation?

The official document recording Japan’s capitulation was the Japanese Instrument of Surrender. It was signed aboard USS Missouri in Tokyo Bay on September 2, 1945, creating the formal legal record of Japan’s defeat.

The instrument stated that Japan accepted the provisions of the Potsdam Declaration and ordered Japanese forces to cease hostilities and surrender. Japanese Foreign Minister Mamoru Shigemitsu signed for the government, while General Yoshijirō Umezu signed for the armed forces. Allied representatives then added their signatures.

The document was not a peace treaty. It established surrender terms and military control; a separate peace settlement, the Treaty of San Francisco, was signed in 1951 and took effect in 1952. This distinction matters because the instrument ended active hostilities, while the later treaty addressed Japan’s postwar legal relations and sovereignty.