Toirdelbach mac Ruaidhi Ó Conchobair
Toirdelbach was the last surviving son of King of Ireland, Ruaidrí Ua Conchobair (died 1198). He is recorded as having had two sons, Conchobar Buide and Brian. His brother, Aedh mac Ruaidri Ó Conchobair, had been King of Connacht from 1228 to his death in 1233, but Toirdelbach himself never reigned. Indeed, no other son or descendant of Ruaidri became king, and before the end of the 13th century his entire line of male descendants had disappeared without trace from the historical record.