How 20th-century immigrants did not have to change their last names in order to become American

Reports of parents’ names in Social Security Application records allow us to quantify at a population level the extent and nature of historical last name changes by immigrants. Our analysis of European, Middle Eastern, and Asian immigrants of the early to mid-20th-century finds that more than 80% kept their last names. Computational linguistic analysis shows that most of those who did change preserved their surname’s ethnic signal, leaving only about 5% of all immigrants trying to disguise their foreign origins. Of these, Jewish immigrants had the highest rate of ethnicity-concealing last name changes; Italian, Japanese, and Chinese immigrants all had the lowest. Our proposed framework helps understand the variation: name changes were rarest where ethnic community networks were densest and where passing as unmarked was least credible—as among visibly non-White immigrants. Our findings challenge the dominant assimilationist narrative that immigrants in this era had to shed their foreign identities to enter the American mainstream. “Becoming White” by adopting an English surname was not a large part of historical immigrant experience. Rather, the overwhelming majority of immigrants chose to openly preserve their ethnic origins. Our results also suggest that nominal record linkage of historical immigrant populations may be more feasible than previously assumed.