Identity is a social construct that has different types, forms and appearances, and as such requires an interdisciplinary conceptual and methodological approach. In relation to the emigrant experience and the targeted group of North American Croats in California, ethnic identity stands out the most because ethnicity is the most important form of social differentiation in American society and the emigrant experience is a dominant characteristic of the American population. In the theoretical part of identity, due to its multidisciplinary and interdisciplinary nature, it is considered from a sociological, cultural-anthropological and psychological perspective with an emphasis on contemporary sociological and sociopsychological research and theories. In this context, the central theoretical and conceptual basis of empirical research in the work is based on social identity theory, role-based identity theory and identity theory. The main goal of the research was to determine the average expression of ethnic identity as one of the components of the social identity of Croats in California and to examine the average importance of the social dimension of identity. The specific goals of the research were to examine the difference between sociodemographic characteristics and the expression of ethnic identity, to examine the connection between the selected social characteristics of the respondents and the expression of ethnic identity, and to determine the average expression of the regional identity of North American Croats in California. In order to achieve the stated goals, that is, to confirm or deny the set research hypotheses, the method and technique of a web survey questionnaire was used within the framework of quantitative methodology on a sample of 226 respondents (N = 226). The main results of the research indicate the existence of a high average expression of ethnic identity among Croatian emigrants in California. Respondents from the second generation of emigration, who have completed the first level of higher education, have a more pronounced ethnic identity, as well as respondents with a right-wing political orientation. Also, the results of the conducted research showed a weak to moderate connection between the selected social characteristics of the respondents and the expression of ethnic identity, and a moderate average expression of regional identity among the studied population.