This article challenges the well-established finding that persons with higher levels of education are more likely to marry outside their own ethnic group. The empirical research upon which that finding is based has been dominated by studies of groups of either immigrant or low socio-economic status. We revisit the question by examining census of population data on two minorities -- Protestants in the Republic of Ireland and the Swedish-speaking Finns -- which are indigenous, traditionally of high socio-economic status and have strong communal institutions. For this type of minority, we reject the hypothesis that persons with higher levels of education are more likely to form intermarriages. We explain our finding in terms of the association between level of education and social integration into the minority sub-culture. Our findings also provide insights into the process whereby after national independence the high socio-economic status of formerly politically dominant minorities is maintained.