Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. UR knowledge of the history of Christianity in the British Isles during the first centuries of its existence is very meagre. We know some thing oi it before the year a.d. 400; and we know a great deal of it after a.d. 600. But about its origin we know nothing, and about the two cen turies which followed the departure of the Roman legions in 409 we know very little. Let us look at the twilight which precedes their departure before attempting to penetrate the darkness which followed it.