This Irish abbot, known as “the master” and “teacher of saints” in the period following St. Patrick, was reported to be from Leinster, where he began establishing monasteries. He traveled to Wales and studied its traditional monasticism, which stressed the superiority of monastic over secular life and the importance of learning. After returning to Ireland, he founded many churches and monasteries, including his great monastery at Clonard on the Boyne, which drew 3,000 disciples, including St. Ciaran of Clonmacnois, St. Columba of Iona and St. Brendan the Voyager. It is uncertain whether he was also a bishop. He died of the plague, probably contracted while he was nursing other victims.