(1892-1949)American banker and government official who, in 1940, became the under secretary of the United States Navy. During World War II (1939-1945) he directed huge naval expansion and procurement programs and was responsible for readying a peacetime navy to meet the enormous demands of global war.(1892-1949) American banker and government official who in June 1940 became assistant to President Franklin D. Roosevelt (1882-1945) and in August became the undersecretary of the navy. During World War II (1939-1945) he directed huge naval expansion and procurement programs and was responsible for readying a peacetime navy to meet the enormous demands of a global war. In 1944 he became the secretary of the navy and helped to build the US fleet into the largest in the world. In 1947 he was appointed as the country's first secretary of defense, in charge of all US military forces, from which position he initiated a reorganization and coordination of the armed services of the United States. In March 1949 Forrestal resigned his post due to what physicians called a depression and shortly thereafter was admitted to the Bethesda Naval Medical Center in Maryland. In May he committedsuicide by jumping out of a hospital window.