He belonged to a branch of the Dal nAraide known as the Uí Echach Cobo in the west part of county Down.
[1] He was the first member of the Dal nAraide to hold the throne since death of Congal Cáech at Mag Roth in 639.
He was of the Ui Echach Coba branch of the Dal nAraide and was the son of Áedán mac Mongain (d.
[2] No mention is made of why he became king but the previous holders, the Dal Fiatach had been guilty of some kin slaying.
Their daughter, Ériu, married Ailill mac Cennfáelad (died 702), King of the Cianachta Glenn Geimin (in what is modern day County Londonderry.)