The Gospel first came to the northern English in 627, when King Edwin of Northumbria was converted by a mission from Canterbury led by Bishop Paulinus, who established his see at York. Edwin’s death in battle in 632 was followed by a severe pagan reaction. A year later, Edwin’s exiled nephew Oswald gained the kingdom, and proceeded at once to restore the Christian mission.

During his exile, Oswald had lived at Columba’s monastery of Iona, where…