Acheson (1893–1971) was not only present at the creation of the postwar world, he was one of its chief architects. He joined the Department of State in 1941 as Assistant Secretary of State for Economic Affairs and, with brief intermissions, was continuously involved until 1953, when he left office as Secretary of State at the end of the Truman years. Throughout that time Acheson's was one of the most influential minds and strongest wills at work. It was a period that included World War II, the reconstruction of Europe, the Korean War, the development of nuclear power, the formation of the United Nations and NATO. It involved him at close quarters with a cast that starred Truman, Roosevelt, Churchill, de Gaulle, Marshall, MacArthur, Eisenhower, Attlee, Eden Bevin, Schuman, Dulles, de Gasperi, Adenauer, Yoshida, Vishinsky, and Molotov.