Who was president of the United States when Japan formally surrendered in 1945?

Harry S. Truman was president of the United States when Japan formally surrendered in 1945.

Truman had become president on 12 April 1945, after Franklin D. Roosevelt died during his fourth term. Truman therefore led the United States during Germany’s defeat, the atomic bombings, Japan’s surrender announcement, and the formal signing ceremony.

On 2 September 1945, Japanese representatives signed the surrender instrument aboard USS Missouri. Truman’s administration had approved the Allied demand for Japan’s unconditional surrender and directed the final wartime use of atomic weapons.

Franklin D. Roosevelt is a common mix-up because he was president during most of World War II and the attack on Pearl Harbor. However, Roosevelt died several months before Japan surrendered. Truman remained president through the early occupation and the transition from wartime mobilization to postwar policy.