James Callaghan

James Callaghan was appointed Chancellor of the Exchequer in 1964 following the victory of the Labour Party, as led by Harold Wilson, in that year's general election. (CM: State of Emergency)

Callaghan later served as the Prime Minister of the United Kingdom from 1976 to 1979. (BFA: Trail of the White Worm)

He was succeeded by Margaret Thatcher of the Conservative Party (BFA: Rat Trap) who held that office from 1979 (DW: Tooth and Claw) until at least 1987 (DW: Father's Day).