On what date did U.S. President Harry Truman announce Japan’s surrender in World War II?

U.S. President Harry Truman announced Japan’s surrender on August 14, 1945.

Truman’s announcement followed Japan’s acceptance of the Allied terms in the Potsdam Declaration. The news reached the United States on August 14, and celebrations began immediately. In Japan and many other countries east of the International Date Line, the announcement was heard on August 15, creating two commonly cited dates for V-J Day.

The announcement did not mark the formal completion of the surrender process. Japan’s representatives signed the Instrument of Surrender aboard USS Missouri in Tokyo Bay on September 2, 1945. That ceremony legally ended Japan’s participation in World War II.

A common mix-up is treating August 14, August 15, and September 2 as interchangeable. August 14 is the date of Truman’s U.S. announcement; August 15 is associated with Emperor Hirohito’s radio address; September 2 is the date of the formal signing.