Frank Forrester Church III (July 25, 1924 – April 7, 1984) was an American politician and lawyer. A Democrat, from 1957 to 1981 he served as a U.S. Senator from Idaho, and is currently the last Democrat to do so. He was the longest serving Democratic senator from the state and the only Democrat from the state who served more than two terms in the Senate. He was a prominent figure in American foreign policy and established a reputation as a member of the party's liberal wing.