Brennan, Joseph (1913–80), politician, was born 14 February 1913 in Donegal, youngest of the twelve children of Frank Brennan, farmer, and Hannah Brennan (née Carr). The family lived at Croagh, near Dunkineely, west Donegal. Educated locally, he began his working life as a freelance journalist with the Irish Press and the Donegal Democrat before establishing himself as an auctioneer, estate agent, and spirit merchant. A useful Gaelic footballer, he played senior football for Donegal. Taking a keen interest in politics while still in his teens, he was elected secretary of the Dunkineely Fianna Fáil cumann in 1931 and first secretary of the west Donegal constituency organisation in 1937. Later he became the director of elections.
During the 1939–45 Emergency he served in the LDF and afterwards in the FCA, retiring as OC of the South Donegal Battalion (later B Coy, 24th Infantry Bn). A Fianna Fáil member of Donegal county council and its subsidiary committees (1945–59), he polled the highest number of first preferences in the November 1949 Donegal West by-election but failed to be elected until the 1951 general election. Representing that constituency until 1961, he subsequently represented Donegal South West (1961–9), Donegal–Leitrim (1969–77), and Donegal (1977–80).
Parliamentary secretary to the minister for finance (1958–61), in charge of the Office of Public Works, he was responsible for the intermediate drainage scheme, under which he was able to have two Donegal rivers, the Duff and the Abbey, drained. Between 1961 and 1965 he was government chief whip and parliamentary secretary to the taoiseach and the minister for defence. Appointed to the cabinet as minister for posts and telegraphs (1965–6), he greatly improved the telephone service in the north-west, giving Donegal and Sligo a direct link to Dublin. As minister for social welfare (1966–9) and minister for labour and social welfare (1969–73), he introduced legislation for the benefit of the elderly and the disadvantaged. Opposition spokesman on industry and commerce (1973–7), he was deputy leader of Fianna Fáil (1975–7) and ceann comhairle (July 1977–July 1980).
He married first Bridget (d. 1940), they had one son and four daughters. In February 1942 he married Margaret M. McDevitt. He died 13 July 1980 at his home, Darney Heights, Darney, Bruckless, Co. Donegal.