Brendan, one of the founding fathers of Christianity in Ireland, was known in legend as a voyager and was thought to have reached the Western Hemisphere long before the Vikings. Columba took Celtic Christianity to Scotland and helped to reestablish it in Wales and in the North and West of England. Columbanus was the great Irish missionary to continental Europe, where he and his followers helped to convert the heathen invaders from the East. Part of this book's fascination is the picture that it gives of the movements of peoples, the shaping of new countries, and the development of ideas during those too-little-known centuries.