One thing it is important hereto have clearly before the mind, as it is very apt to be overlooked. At the time of St. Columba’s ministry, England, which during the lifetime of St. Patrick had been Roman and Christian, had now under the iron flail of its Saxon conquerors lapsed back into Paganism. Ireland, therefore, which for a while had made a part of Christendom, had been broken short off by the heathen conquest of Britain. It was now a small, isolated fragment of Christendom, with a great mass of heathenism between. We can easily imagine what a stimulus to all the eager enthusiasts of the Faith the consciousness of this neighbourhood must have been; how keen the desire to rush to the assault and to replace the Cross where it had been before.
That assault was not, however, begun by Ireland; it was begun, as every one knows, by St. Augustine, a Roman priest, sent by Pope Gregory, who landed at Ebbsfleet, in the Isle of Thanet, in the year 597—thirty-two years after St. Columba left Ireland. If the South of England owes its conversion to Rome, Northern England owes its conversion to Ireland, through the Irish colony at Iona. Oswald, the king of Northumbria, had himself taken refuge in Iona in his youth, and when summoned to reign he at once called in the Irish missionaries, acting himself, we are told, as their interpreter. His whole reign was one continuous struggle with heathenism, and although at his death it triumphed for a time, in the end the faith and energies of the missionaries carried all before them. After the final defeat of the Mercians, under their king Penda, at Winwoed, in 655, the struggle was practically over. Northern and Southern England were alike once more Christian.