Brádaigh was born on 2 October 1932 in Longford, Irish Free State. He was raised in Dublin, Irish Free State. Brádaigh studied at St. Mel's College and at University College Dublin. He was married to Patsy O'Connor until his death in 2013. They had no children. Brádaigh died on 5 June 2013 in Roscommon, Republic of Ireland from a short illness, aged 80.