R. W. Morgan proposes that St. Paul introduced Christianity to Celtic Britain, and that the Christian church and the first ancestors of the modern royal family were established several centuries prior to what is conventionally thought.

Although the ideas and theories of R. W. Morgan are discredited and unpopular in the modern day, his investigations into the early church history of Britain are interesting and thought-provoking. Following on from his research of ancient sources, Morgan proposes the concept of the apostolic church - a Christianity developed independent of the later, Roman church - was more compatible with the existing Druidic order of Britain and appealing to the native population. With this line of reasoning, the idea Paul founded Christianity in Britain is considered plausible.

The idea that St. Paul and his retinue of early Christians journeyed across the Roman Empire to Great Britain was not new. The possibility was raised by scholar Edward Cardwell, who dismissed the event as unsubstantiated speculation. There is no evidence that Christianity spread to the British Isles so soon after the life of Christ - St. Paul died in the 60s AD. Morgan also introduces the idea that England's monarchs are related to the early Christians, asserting that Boudica and Caratacus converted to Christendom.