Sheldon Gwendolyn, The Conversion of the Vikings in Ireland from a Comparative Perspective, Thèse de doctorat soutenue en 2011, (dir. A. Orchard, Université de Toronto)
The history of the Viking invasions in England and what is now France in the ninth and tenth centuries is fairly well documented by medieval chroniclers. The process by which these people adopted Christianity, however, is not. The written and archaeological evidence that we can cobble together indicates that the Scandinavians who settled in England and Normandy converted very quickly. Their conversion was clearly closely associated with settlement on the land. Though Scandinavians in both countries expressed no interest in Christianity as long as they engaged in a Viking lifestyle, characterized by rootless plundering, they almost always accepted Christianity within one or two generations of becoming peasants, even when they lived in heavily Scandinavian, Norse-speaking communities. While the early history of the Vikings in Ireland was similar to that of the Vikings elsewhere, it soon took a different course. While English and French leaders were able to set aside land on which they encouraged the Scandinavians to settle, none of the many petty Irish kings had the wealth or power to do this. The Vikings in Ireland were therefore forced to maintain a lifestyle based on plunder and trade. Over time, they became concentrated into a few port towns from which they travelled inland to conduct raids and then exported what they had stolen from other parts of the Scandinavian diaspora. Having congregated at a few small sites, most prominently Dublin, they remained distinct from the rest of Ireland for centuries. The evidence suggests that they took about four generations to convert. Their conversion differed from that of Scandinavians elsewhere not only in that it was so delayed, but also in that, unlike in England and Normandy, it was not associated with the re-establishment of an ecclesiastical hierarchy. Rather, when the Scandinavians in Ireland did convert, they did so because they were evangelized by monastic communities, in particular the familia of Colum Cille, who had not fled from foundations close to the Viking ports. These communities were probably driven by political concerns to take an interest in the rising Scandinavian towns.