This dissertation investigates the relationship between colonialism and settlement. It examines three episodes of colonialism in two case-study regions facing each other across the North Channel, corresponding to eastern Northern Ireland (‘Ulidia’), and mid-western Scotland (‘Ergadia’). By comparing different forms of colonial activity across several time periods and between two regions, the dissertation improves our understanding of colonialism and migration across time and space. The first episode involved the purported elite migration of the Dál Riata from northeast Ireland to western Scotland c.AD500. The second involved the arrival in both regions and beyond of raiders and settlers from Scandinavia c.AD790–850. The third involved a group of settlers mainly from England and Wales, who established the earldom of Ulster as part of a wider expansion into Ireland c.AD1167–1200.

The analysis of the continuities and discontinuities in both case studies was based on a series of chronological syntheses drawing together the archaeological, architectural and documentary evidence for settlement in each region c.800BC–AD1400. It was further augmented by employing burial and toponymic evidence as proxies for settlement. Combined with the textual narrative, the archaeological syntheses enabled an examination of, firstly, whether colonial activity actually occurred, and, secondly, the form of colonialism that took place and the processes that lay behind it. To structure the interpretation, each colonial episode was broken down into contact, expansion, consolidation and domination phases, with further phases based on their socio-political and transcultural outcomes.

The Dál Riata episode was probably not an example of colonialism. The documentary evidence was found to be unreliable and related to a late reshaping of a usable past. Moreover, there was no visible shift in settlement practices identifiable with incoming colonists. The Scandinavian episode differed on either side of the North Channel. There is no evidence that settlers got beyond a consolidation phase in Ulidia, with very little impact on traditional burial practices, settlement, and language use. Conversely, in Ergadia a major shift was apparent in secular settlement and burial practices. The appearance of a large number of Old Norse placenames also indicates settlement involving several social orders. This heavily influenced the socio-political makeup of the region to at least the fourteenth century. In the third episode, a domination phase was also reached in Ulidia. It involved the establishment of a new extractive elite, with shifts in settlement and toponymic, but not burial, practice.