Son of a Celtic chieftain, possibly from the area of Strathclyde, Scotland; related to Saint Asaph of Llanelwy. Founded monasteries in Gwynedd and Flintshire. First bishop of Bangor, Wales, consecrated by Saint Dubritius. An evangelist and excellent shepherd of his people. Worked with Saint David of Wales. The cathedral of Bangor and several other churches were named in his honour.