Harry S. Truman announced the atomic bombing of Hiroshima and urged Japan to surrender in August 1945.
Truman became U.S. president on April 12, 1945, after Franklin D. Roosevelt died. He inherited responsibility for the final phase of the war against Japan, including decisions about military operations and the use of the atomic bomb.
On August 6, 1945, the White House issued Truman's statement announcing that an atomic bomb had been used against Hiroshima. The statement warned Japan that further attacks could follow unless it accepted the Allied demand for surrender.
Truman was president when Japan announced surrender on August 15 and when the formal instrument was signed on September 2. A frequent mistake is attributing the decision to Roosevelt, who had died before the Hiroshima bombing, or to General MacArthur, who led the surrender ceremony but was not the U.S. president.