- December 31, 1969
Francis Thomas Aiken (13 February 1898 – 18 May 1983) was an Irish revolutionary and politician. He was chief of staff of the Anti-Treaty IRA at the end of the Irish Civil War.
Aiken later served as Tánaiste from 1965 to 1969 and Minister for External Affairs from 1951 to 1954 and 1957 to 1969. Previously he had held the posts of Minister for Finance from 1945 to 1948, Minister for the Co-ordination of Defensive Measures 1939 to 1945, Minister for Defence from 1932 to 1939, and was also Minister for Lands and Fisheries from June–November 1936.
He was a Teachta Dála (TD) for the Louth constituency from 1923 to 1973, making him the second longest-serving member of Dáil Éireann and the longest-serving cabinet minister. Originally a member of Sinn Féin, he was later a founding member of Fianna Fáil.