Born to a rich Roman family in Britain, he was well educated but was captured at age 15 during a slave raid on the west coast of Britain. An Irish raider sold him as a slave in Ireland, where he herded animals on Slieve Mish (Sliabh Mis) mountain, near Belfast. After six years of this, he experienced a profound spiritual awakening, escaped, and returned to his family but with the intention of returning to Ireland and converting it to Christianity.