Penda stood supreme in Britain.  Heathenism triumphed with him.  If Wessex did not own his overlordship as it had owned that of Oswald, its king threw off the Christian faith which he had embraced but a few years back at the preaching of Birinus.  Even Deira seems to have owned Penda’s sway.  Bernicia alone, though distracted by civil war between rival claimants for its throne, refused to yield.  Year by year the Mercian king carried his ravages over the north; once he reached even the royal city, the impregnable rock-fortress of Bamborough.  Despairing of success in an assault, he pulled down the cottages around, and piling their wood against its walls fired the mass in a fair wind that drove the flames on the town.  “See, Lord, what ill Penda is doing,” cried Aidan from his hermit cell in the islet of Farne, as he saw the smoke drifting over the city, and a change of wind—­so ran the legend of Northumbria’s agony—­drove back the flames on those who kindled them.  But burned and harried as it was, Bernicia still clung to the Cross.  Oswiu, a third son of AEthelfrith, held his ground stoutly against Penda’s inroads till their cessation enabled him to build up again the old Northumbrian kingdom by a march upon Deira.  The union of the two realms was never henceforth to be dissolved; and its influence was at once seen in the renewal of Christianity throughout Britain.  East-Anglia, conquered as it was, had clung to its faith.  Wessex quietly became Christian again.  Penda’s own son, whom he had set over the Middle-English, received baptism and teachers from Lindisfarne.  At last the missionaries of the new belief appeared fearlessly among the Mercians themselves.  Penda gave them no hindrance.  In words that mark the temper of a man of whom we would willingly know more, Baeda tells us that the old king only “hated and scorned those whom he saw not doing the works of the faith they had received.”  His attitude shows that Penda looked with the tolerance of his race on all questions of creed, and that he was fighting less for heathenism than for political independence.  And now the growing power of Oswiu called him to the old struggle with Northumbria.  In 655 he met Oswiu in the field of Winwaed by Leeds.  It was in vain that the Northumbrian sought to avert Penda’s attack by offers of ornaments and costly gifts.  “If the pagans will not accept them,” Oswiu cried at last, “let us offer them to One that will”; and he vowed that if successful he would dedicate his daughter to God, and endow twelve monasteries in his realm.  Victory at last declared for the faith of Christ.  Penda himself fell on the field.  The river over which the Mercians fled was swollen with a great rain; it swept away the fragments of the heathen host, and the cause of the older gods was lost for ever.

[Sidenote:  Oswiu]