It could not be expected that, while there were still within the Roman frontiers many outlying districts where the new religion had not penetrated, the western churches could conceive the design of making any systematic attempt to convert the folks who lived beyond the borders of the Empire. The first duty of the bishops of Gaul and the bishops of Britain, if they undertook any missionary work, was to extend their faith in the still heathen parts of their own provinces. The single conspicuous case in which it reached a northern people, independent of the Empire, is significant, for it exhibits the kind of circumstances which helped this religion to travel. The conversion of the West Goths in Dacia was not inaugurated by any missionary zeal on the part of the Church, but came to pass through the means of Christian captives whom the people had carried off in their invasions of Asia Minor in the middle of the third century. The “apostle” Wulfilas, whose work led to the general conversion of the Goths, sprang from a Cappadocian family which had thus been led into captivity, and had lived for two generations in Gothic land. Gothic in spirit and sentiment, as he was Gothic in name, he devoted himself to spreading the gospel of the Christians among his people. His work was recognised and supported at Constantinople, but the fact remains that the conversion of the Goths was due to the hostilities which had brought Christian captives to their land, and not to missionary enterprise of the Church. The part which captives played in diffusing a knowledge of their religion is, in this instance, strikingly exemplified. The conversion of the kingdom of Iberia under Mount Caucasus is another case. The story that it became Christian in the reign of Constantine through the bond-slave Nino, who is still revered there as the “enlightener and apostle of Georgia,” rests upon evidence only two generations later, and must have a foundation in fact.[3] And even if the tale is not accepted literally, its existence illustrates the important part which Christian captives played in the diffusion of their creed. This is expressly observed by the author of the treatise _On the Calling of the Gentiles_. “Sons of the Church led captive by enemies made their masters serve the gospel of Christ, and taught the faith to those to whom the fortune of war had enslaved them.”[4] The same nameless writer, who composed his work in the fifth century, notices another channel by which knowledge of his religion was conveyed to the barbarians. Foreign soldiers, who enlisted in the army of the Empire, sometimes came under Christian influences in their garrison stations, and when they returned to their own homes beyond the Imperial frontier they carried the faith with them.[5]