Oliver J. Flanagan (22 May 1920 – 26 April 1987) was an Irish Fine Gael politician who served in Dáil Éireann for 43 years and was Minister for Defence for six months. Prior to his election to the Dáil, Flanagan had been Secretary of a local branch of the Fianna Fáil party. He was elected to the Dáil fourteen times between 1943 and 1982, topping the poll on almost every occasion. He was Father of the Dáil from 1981 until his retirement in 1987, and he remains one of the longest-serving members in the history of the Dáil.
Flanagan was a social conservative, who famously claimed that "there was no sex in Ireland before television". A notorious anti-semite, he used his maiden speech in the Dáil, on 9 July 1943, to urge the government to "rout the Jews out of this country".
Nonetheless, he was consistently popular in his own constituency, largely because of the attention he paid to individual voters' petitions and concerns. He has been described as "one of the cutest of in the history of the Dáil".
Flanagan was born in Mountmellick, County Laois, on 22 May 1920. He was educated at Mountmellick Boys National School and worked as a carpenter and auctioneer. He was member of the Catholic fraternal organisation the Knights of Saint Columbanus, and in 1978 was conferred a Knight of the Order of St. Gregory the Great by Pope John Paul I, given in Rome on September 20, 1978.
Flanagan first held political office in 1942 when he was elected as a councillor to Laois County Council, a position he would hold for almost forty-five years.
He was first elected to Dáil Éireann as an Independent Teachta Dála for the Laois–Offaly constituency at the 1943 general election — the third youngest person ever to have been elected to the Dáil until that time. He had stood for election on the Monetary Reform Party ticket, an anti-semitic and Social Credit party confined to his own constituency which proposed reducing the supposed Jewish stranglehold on the financial system.