American President A Reference Resource ↑ Harry S. Truman Front PageJames V. Forrestal (1947–1949): Secretary of DefenseJames Vincent Forrestal was born February 15, 1892, in Beacon, New York, attending both Dartmouth College and Princeton University. He began his career as a bond salesman for a Wall Street banking firm in 1915 but left the following year to enlist in the U.S. Navy. After the war, he returned to the financial sector and, in 1938, assumed the presidency of William A. Read & Company, becoming one of the most important bond investors on Wall Street. Forrestal served for six weeks as an administrative assistant to President Franklin D. Roosevelt in 1940 before being named undersecretary of the Navy (1940-1944). He became secretary of the Navy in 1944 and remained in that post following Roosevelt's death, overseeing the transition of the Departments of War and Navy into a comprehensive Department of Defense -- a bureaucratic reorganization mandated by the National Security Act of 1947. Forrestal became the nation's first secretary of defense, serving President Harry S. Truman in that capacity from 1947 until he resigned in 1949. Shortly after his resignation, Forrestal was hospitalized because of severe depression. On May 22, 1949, he committed suicide when he allegedly climbed out of a window to hang himself and fell to his death from the sixteenth floor of the Bethesda Naval Hospital in Maryland.