What was the official document called that formalized Japan’s surrender in 1945?

The Japanese Instrument of Surrender was the official document that formalized Japan’s capitulation in World War II. It was signed aboard USS Missouri in Tokyo Bay on September 2, 1945.

The document stated that Japan accepted the provisions of the Potsdam Declaration and ordered Japanese forces to cease hostilities. It also required Japanese forces to disarm and surrender to designated Allied commanders. The instrument therefore converted Japan’s announced decision into a formal act of surrender.

Mamoru Shigemitsu signed for the Japanese government, followed by General Yoshijiro Umezu for Imperial General Headquarters. General Douglas MacArthur then signed for the Allied Powers, with representatives of several Allied nations following him.

The Instrument of Surrender was not the same as the later Treaty of San Francisco. That treaty, signed in 1951 and effective in 1952, formally ended the state of war between Japan and many Allied countries and restored Japan’s sovereignty.