He was a member of the Dal Fiatach and nephew of Baetan mac Cairill (died 581) of Ulaid.
His first mention in the Irish annals is the battle of Cúl Caíl (possibly Kilkeel, modern County Down) in 601, where he was defeated by Fiachnae mac Baetain of the Dal nAraide.
He had two wives:[5] Cumne Dub was the daughter of Furudrán mac Béicce of the Uí Tuirtri.
Cumne (Cummíne) Find was the daughter of Báetán Cáech of DalnAraide and sister of Fiachnae mac Baetan.
She was the mother of Máel Cobo mac Fiachnae (died 647), a king of Ulaid and a son named Suibne.