What document formally ended Japan’s hostilities with the Allied powers in World War II?

The Japanese Instrument of Surrender formally ended Japan’s hostilities with the Allied powers in World War II.

Japan signed the document aboard USS Missouri in Tokyo Bay on September 2, 1945. It set out Japan’s acceptance of the Potsdam Declaration and required Japanese forces to cease hostilities and surrender to the Allied powers.

The Potsdam Declaration was an earlier Allied ultimatum, issued in July 1945, rather than the final surrender document itself. Japan’s acceptance of that declaration led to the formal ceremony, where representatives signed the printed instrument on behalf of the Japanese government and military headquarters.

The signing ended the fighting, but it did not immediately create a permanent peace treaty between Japan and every Allied country. The later Treaty of San Francisco, which took effect in 1952, formally restored Japan’s sovereignty after the occupation. This difference explains why the surrender instrument and the peace treaty are often mistakenly treated as the same document.