Ó Caoláin was born in Monaghan in 1953. He was educated at St. Mary's CBS, Monaghan. He was a bank official with the Bank of Ireland in the 1970s, and worked in a number of towns, including Ballinasloe. He became a senior bank official but then left the bank to concentrate on politics. Ó Caoláin is married to Briege McGinn and they have four daughters and one son. Ó Caoláin underwent successful cardiac surgery early in 2007. On 19 June 2007, it was reported that he was rushed to hospital, but he was released shortly thereafter and has since made a full recovery.
Political career
He has been active in republican circles since the 1970s. He was Director of Elections in the Anti H-Block campaign of 1981, which sawKieran Doherty elected as a TD for the Cavan–Monaghan constituency. Between 1982 and 1985, he was general manager of the republican newspaper An Phoblacht. Ó Caoláin's first political success came in 1985 when he was elected to Monaghan County Council as a Sinn Féin County Councillor. In 1989, loyalist paramilitaries attempted to kill him and another Sinn Féin Councillor. At the 1984 and 1989 European Parliament elections he stood unsuccessfully in the Connacht–Ulster constituency. Ó Caoláin represented Sinn Féin at the Forum for Peace and Reconciliation in Dublin in the mid-1990s. In 1996, he was an unsuccessful candidate in the Northern Ireland Forum election in Newry and Armagh. He was also a member of the Sinn Féin negotiations team during the talks which led to the Good Friday Agreement in 1998. At the 1997 general election he was elected to Dáil Éireann for the Cavan–Monaghan constituency, making him the first Sinn Féin TD elected since 1957 and the first Sinn Féin TD to take his seat at Dáil Éireann in Leinster House. He was subsequently re-elected at the 2002 general election and was joined by four other Sinn Féin deputies. He was re-elected at the 2007 general election, 2011 general election and 2016 general election. Ó Caoláin is currently Sinn Féin's Spokesperson on Health and Children. He accepts the average industrial wage and donates the remaining portion of his TD salary to his party. On 7 March 2018, Ó Caoláin announced that he would not contest the next general election.
