Conn Ó Néill (sometimes anglicised as Con or Constantine O'Neill) was the titular head of the Clandeboye O'Neill dynasty.
He was born in the Parish of Saint Catherine, Dublin, the only son and successor of the previous Head of the House, Phelim (Felix) O'Neill by his first marriage to Catherine Keating.
He lived in Dublin, County Dublin.
[1][2] He married Cecilia O'Hanlon (Ireland, Leinster, Archbishopric of Dublin, Cashel, daughter of Captain Féilim Ó hAnluain (in English Phelim or Felix O'Hanlon) and wife, and had issue, three sons and six daughters: