Prescott Bush served as a captain of artillery (the same rank held by Harry S. Truman) during World War I. After the war he became a businessman, eventually settling in Connecticut and working in New York's banking industry. He was elected U.S. senator as a Republican from Connecticut in 1952, following the mid-term death of senator Brien McMahon. Bush was reelected in 1956 and retired after that term ended in 1963.