People from the British and Irish Isles have migrated to all corners of the globe for centuries. This volume of essays offers the first integrated study of the formation of diasporas from the islands of Ireland and Britain. It presents the reader with ways in which the examples and experiences of the constituent nations and peoples of those islands compare, as well as forming a critically discursive examination of the similarities, differences, tensions and possibilities of such an integrated approach. The mass movements discussed range widely, including English, Irish, Scots, Welsh, and also sub-national groups: the Cornish, people from manufacturing towns in the Midlands, and groups from remote parts of the Highlands, both Catholic and Protestant. Yet wherever they went, these migrants co-mingled, blended and blurred. In so doing, they created new identities as neo-Britons, neo-Irish, neo-Scots - persons who were colonials, new nationals, and yet still linked to their old country and home nations. The volume highlights the varying foundations and evolution of different diasporas, whether rooted in a common culture, ideology or religion, or a collective exile, flight or disagreement, and explores each nation's recognition of their own diaspora. This book is a tool of inquiry into migrant worlds, and will be of particular interest to historians of migration and diaspora, historians of the British and Irish Isles, and also to historians of the migrants' destination countries that are explored in the volume.