The present revival of Catholicism in Wales would be incomplete without the old devotion to the early Welsh Saints, of whose constant intercession for their native land we now begin to see the fruit. Though their cultus was forbidden at the Reformation, they have kept their place in the affection of the Welsh people; and the increased knowledge of their lives gained by modern scholars is a valuable help in restoring their rightful place in popular devotion. To the historian their chief importance is their formative influence on the Welsh nation, which, as is being increasingly recognised, grew out of Celtic monasticism, of which these Saints were the founders. Under Roman rule British Christianity had its centres in the cities and its organisation was interwoven with that urban life which was the framework of the imperial system. The decay of urban life after the departure of the Legions induced a period of stagnation in British Christianity from which it was rescued only by the monastic movement, which introduced a new organisation better able to adapt itself to the tribal system now replacing imperial administration. Thus it was Celtic monasticism which fused the British tribes and the remnants of Roman culture into a spiritual unity so that, from being a merely geographical term in Roman times, by the 8th century Britanni had become the name of a nation. That its ethos even today is essentially religious is the enduring legacy of the early Welsh Saints. It is not surprising, therefore, that the increasing study of their lives by modern scholars has been prompted by historical rather than by religious motives.