Childhood exposure to ethnic outgroups predicts interethnic marriage

Scholars posit that childhood exposure to ethnic outgroups may durably improve intergroup relations. However, few studies to date track the consequences of childhood experiences across multiple decades. Moreover, existing research focuses on majority populations and largely overlooks the impact of exposure for minorities. Using linked geocoded US census records from 1880 to 1900/1910, we examine childhood outgroup exposure and subsequent marriage patterns for over 400,000 American, German and Irish men. To account for residential self-selection, we use machine-learning to identify “ethnic” neighborhoods and compare individuals living within the same residential contexts but having different next-door neighbors. In majority-minority dyads, outgroup exposure is consistently associated with a higher likelihood of marrying a member of that group, as well as a lower likelihood of ingroup marriage. The evidence is less robust for minority-minority dyads but nonetheless supports an overall pattern wherein childhood experiences can serve to erode ethnic group boundaries.