After the success of the Kentish mission had received this terrible check, the work of evangelization was carried on by efforts that were more or less independent of it. East Anglia was finally converted by a Burgundian priest named Felix, who was consecrated bishop by Honorius, archbishop of Canterbury, and fixed his see at Dunwich, once on the Suffolk coast. The Italian, Birinus, who was consecrated in Italy, brought the Gospel to the West Saxons, and received Dorchester, in Oxfordshire, for the place of his see. Northumbria was evangelized by Celtic missionaries who were not in communion with Rome and Canterbury. About the middle of the sixth century the Irish Scot, Columba, founded the monastery of Iona. He and his companions preached the Gospel to the northern Picts and the Scots of the western isles, and Iona became a centre of Christian light. During the reign of Eadwine, Oswald and Oswiu, princes of the rival Bernician line, had found shelter in Iona. Oswald returned to become king of Bernicia shortly after the death of Eadwine, and before long brought Deira also under his dominion. As soon as he had gained possession of the kingdom of Bernicia, he sent to Iona for missionaries to instruct his people. Aidan, a missionary from Columba's house, came to him, and so it came to pass that Bernicia received Christianity from Celtic teachers, from Aidan and his fellow-workers. Oswald warmly seconded their efforts, and fixed the see of Aidan, who was in bishop's orders, in Lindisfarne, or Holy Isle, not far from Bamborough, where he resided; for though he ruled over both the Northumbrian kingdoms, and completed the minster at York, he made his home in the North, among his own people. Bernicia thus became the stronghold of Celtic Christianity under the rule of the kings of the house of Ida, while the Christians of Deira were naturally more inclined to the Roman usages which had been introduced by Paulinus and practised by Eadwine and his queen. Aidan built a monastery at Lindisfarne, and peopled it with monks from Iona. This gave him a good supply of clergy, and the work of evangelization prospered and took deep root. The greatness of Oswald provoked Penda to renew his struggle with the northern kingdom, and the Northumbrian king was defeated and slain at Maserfield. As his foes closed round him he prayed for their conversion. His words sank deeply into men's hearts. "'May God have mercy on their souls,' said Oswald, as he fell to earth," was a line handed down from generation to generation. From his hermit's retreat on Farne Island, Aidan beheld the thick clouds of smoke rise from the country round Bamborough, and cried, "Behold, Lord, the evil that Penda doeth!" Still the work of God went on; and when Oswiu came to the throne the prayer of Oswald received its answer, for a marriage between his house and the house of Penda led to the evangelization of the Mercians and Middle Angles by the monks of Iona.