On what date did the formal surrender of Japan take effect aboard USS Missouri in Tokyo Bay?

The formal surrender of Japan took effect on September 2, 1945, aboard USS Missouri in Tokyo Bay. Japanese representatives signed the Japanese Instrument of Surrender shortly after 9 a.m. Japan Standard Time, and the document became effective at 9:25 a.m.

This date is commonly called Victory over Japan Day, or V-J Day, although some countries use August 15 for the earlier announcement of Japan’s acceptance of the Allied terms. On August 15, Emperor Hirohito’s recorded address told the Japanese public that Japan had accepted the Potsdam Declaration. The September ceremony was the legal and ceremonial conclusion of the war with Japan.

The signing followed Japan’s military collapse after the atomic bombings of Hiroshima and Nagasaki, the Soviet declaration of war, and intense internal debate in Tokyo. The ceremony aboard Missouri lasted about 23 minutes and was attended by representatives of nine Allied powers. It is often confused with the August radio broadcast, but the two events occurred on different dates.