Cyrus Roberts Vance was the United States Secretary of State under President Jimmy Carter from 1977 to 1980. He approached foreign policy with an emphasis on negotiation over conflict and a special interest in arms reduction. In April of 1980, Vance resigned in protest of Operation Eagle Claw, the secret mission to rescue American hostages in Iran. He was succeeded by Edmund Muskie.
Vance was the nephew of 1924 Democratic Presidential Candidate and noted lawyer John W. Davis.