Christianity arrived early in the British Isles: an Aristobulus is recorded as a ‘bishop’ there in the 1st century, soon after the Roman conquest. By the late 4th century, Ireland had produced the influential theologian Pelagius, who rejected predestination and believed in the doctrine of free will. The collapse of Roman power and subsequent pagan Saxon invasions made Britain an attractive destination for prospective saints looking to spread the Christian message. Many trained in France, like St Patrick; originally from a well-to-do Anglo-Roman family, he was enslaved by Irish pirates and converted to Christianity. St Brigit, who founded the monastery at Kildare and a string of churches in central Ireland was, like St Patrick, enslaved in childhood, a sign of the lawlessness of the times. Patrick’s initial mission was to combat Pelagianism but he went on to establish the foundations of the Church in Ireland. Later, Irish St Columba founded the monastic community of Iona, while St Cuthbert converted the peoples of the Anglo-Scottish borders.