Unlike the native British, the Anglo-Saxons were not Christian but worshipped pagan gods. In AD 597 Pope Gregory sent a monk, Augustine, from Rome to convert the Anglo-Saxons. He landed in Kent, where the king, Ethelbert, had a Frankish Christian wife. Ethelbert was baptised and Augustine was allowed to found a monastery at Canterbury. In 601 he was ordained archbishop there.

Gregory wanted to set up archbishoprics in London and York, but they lay in hostile territories. A see (the seat of an archbishop) was established at Rochester (Kent) in 604, and after the East Saxons had been converted, a cathedral to St Paul was dedicated for them in London. The early conversions were not always secure. King Rædwald of East Anglia was baptised, but continued to worship his pagan gods. King Eadwine of Northumbria welcomed the Roman missionary Paulinus in 627 and was baptised, but when he died five years later, his successors drove Paulinus out.

Finally, in 669, the Pope sent a new archbishop, Theodore, a scholar and a firm administrator. During his 20-year rule, he reorganised the Church government and oversaw a golden age of scholarship in English monastic life. Theodore also established a cathedral school at Canterbury, which became a centre of learning and attracted many young scholars.