The study concerns two minority groups, the Finnish Roma and the Swedish Travellers, and their changing relationship with the ‘peasants’ - ie. the mainstream sedentary population - in a period of economic modernization and nation-state building. Leaning on a wide array of qualitative material, the research forms an analysis of interethnic relations, with a particular focus on micro-level interaction, conflicts and boundary drawing. As a socio-historical research, it aims to broaden a topic which has conventionally been approached from political and cultural perspectives. Contrasting with an ‘isolation thesis’ implicit in much of the previous literature, the study found that the Roma and Traveller populations were in the research period tied into constant interaction with the sedentary rural population. Yet, close everyday interaction and established networks co-existed with extremely strong ethnic differentiation, upheld from both sides of the divide. This was clear in relation to those transgressing the ethnic boundary, be it through inter-ethnic matrimony, being raised as a foster children, ‘settling down’, etc. Despite constant re-adaptations, the Swedish Travellers and particularly Finnish Roma seem to have lost much of previous occupational diversity during the research period. Upheavals and social stratification in the rural society wiped out old niches and the established local positions connected to this. A process of marginalization was reinforced by local vagrancy- and social control. These followed a circular logic, which continuously pushed out those already seen as illegitimate and unwanted. Local authorities acted as powerful boundary enforcers, dramatically reducing the options of those labelled as ‘Gypsies’ or ‘Tartars’. The rise of nationalist framework problematized the position of the Roma and the Travellers further. The emergence of ‘print capitalism’ was accompanied by the public stigmatization of the latter as deviants and degenerates. In the local level, the ‘Gypsy’ and ‘Tattare’ ‘questions’ were entwined with power struggles and class tensions, with freeholding peasants particularly eager to exclude Roma and Travellers, both on national and local level. While the empirical focus of the thesis is on the Finnish case, comparison with Sweden points to the intertwining of social separation and cultural differentiation. In both cases, the interlocking of social-, ethnic- and ‘racial’ differentiation, together with status of illegitimacy, produced what could be called ‘enforced ethnicity’.