The conversion of the Anglo-Saxons was not a purely peaceful affair. It was a time of military conflict, and the spread of Christianity was often closely tied to the expansion of royal power. In many cases, kings who adopted Christianity did so not merely out of spiritual conviction but also because it provided political and military advantages. Aligning with the Roman Church allowed these rulers to solidify their legitimacy, attract support from Christian Europe, and enhance their power.

For example, King Æthelberht of Kent, by converting to Christianity, secured the loyalty of the powerful Christian forces across the continent, and this aided him in his conflicts with neighboring tribes. Similarly, King Oswald of Northumbria, who ruled from 634 to 642, used his Christian faith to unite his kingdom and defeat rival kingdoms. Oswald’s military victories, as well as his efforts to spread Christianity, were a clear example of how the sword and the cross were intertwined during the early stages of the conversion process.

The Conversion of Northumbria and the Synod of Whitby

One of the most pivotal moments in the Anglo-Saxon conversion came with the Synod of Whitby in 664 CE. The synod was called by King Oswiu of Northumbria, who sought to resolve a dispute between the Roman and Celtic traditions of Christianity. The question at hand was which form of Christianity should dominate the Anglo-Saxon kingdoms: the Roman model, which had been brought by Augustine and his successors, or the Celtic Christian practices of the Irish and their missionary bishops, such as Columba of Iona.

The dispute had deep political and religious implications, as Oswiu’s decision would affect the unity of his kingdom and the future of Christianity in England. At the Synod of Whitby, Oswiu sided with the Roman position, partly due to the influence of his wife, Eanfled, who had been raised in a Roman Christian environment. This decision marked the beginning of Roman-style Christianity becoming the dominant force in Anglo-Saxon England, overshadowing the earlier Celtic Christian traditions shutdown123