I heard a very interesting paper at an American Council of Irish Studies conference by a scholar who had traced the very early experience of Gaeltachta persons who were transported or kidnapped to work in the sugar plantations of Barbados. This occasionally included entire villages. Apparently this was sufficiently common that, in the west of Ireland, the term for such kidnapping was "to be 'Barbadozed.'" The Caribbean term "Redlegs" (meaning poor whites, similar to the "Rednecks" of the US South) comes from the presence of the descendents of the same people.

This scholar theorized that the origin of "Black Irish" (which I've commonly heard as a reference to persons in the west of Ireland with swarthy skin, dark curly hair, and/or dark eyes) might be in the offspring of mixed-race liaisons in Barbados who later returned to Ireland. She made a pretty convincing argument.