It is likely that his reign ended as a result of his defeat at the hands of the Picts of Fortriu, led by Talorgan mac Fergusa, brother of Óengus, at "Cnoc Cairpri in Calathros at Etarlinde".
Crese que o seu reinado rematou como resultado da derrota a mans dos pictos de Fortriu, liderados por Talorgan mac Fergusa, irmán de Óengus I, en "Cnoc Cairpri in Calathros at Etarlinde".