Which U.S. president approved the Potsdam Declaration demanding Japan’s surrender in 1945?

Harry S. Truman approved the Potsdam Declaration demanding Japan’s surrender in 1945.

Truman had become president of the United States on April 12, 1945, after Franklin D. Roosevelt died. At the Potsdam Conference in Germany, Truman represented the United States while the Allied leaders discussed the war’s final phase and the future of Europe and Asia.

The declaration was issued on July 26 by the United States, the United Kingdom, and China. It demanded Japan’s unconditional surrender and warned of severe consequences if Japan refused. Truman was also informed during the conference that the United States had successfully tested an atomic bomb, though the declaration itself did not name the weapon.

Truman later authorized the atomic bombings of Hiroshima and Nagasaki. Japan announced its acceptance of the Allied terms in August. The formal surrender followed aboard USS Missouri on September 2, 1945, during Truman’s presidency.