An individual’s ethnic identity stems from a sense of belonging, to a greater or lesser degree, to a group with its own distinct characteristics. Since censuses and many quantitative surveys contain questions about ethnic origin, the extent to which responses match respondents’ ancestry can be examined. Using genealogical information about nearly 400 individuals residing in the Gaspésie region of eastern Quebec, this study compared participants’ reported origins with the origins of their first immigrant ancestors to have settled in Quebec. The participants’ genealogies were reconstructed, their immigrant ancestors identified and their geographical origins documented. The results show that the origins reported by respondents in the Gaspé Peninsula are consistent with their ancestry. Although almost all the participants have immigrant ancestors of various origins, in the majority of cases their reported group of origin is also the one most represented by those ancestors. Interestingly, when their paternal and maternal origins are different, respondents are more likely to identify with their paternal ones. Despite a diverse history of settlement and considerable intermingling of ethnic groups, inhabitants of the Gaspésie region have maintained a sense of ethnic identity that still reflects a certain demographic and genetic reality today.