Family, Migration and Belonging in Japan’s Nationality Act

Development summary

Sara Park’s book chapter, published on 19 August 2026, explores Japan’s Nationality Act at the intersection of family, migration and national identity. It considers the relationship between the jus sanguinis regime and family registration and marital status, the effect of the 1985 reform and 2008 amendment on parenthood and parent-child relationships, and current debates on multiple nationality.

The chapter combines legal history with sociological research on family and national identity, policy debates, materials from organisations supporting multicultural families, case studies and legal controversies. Park argues that Japanese nationality law does more than regulate membership of the state: it also shapes normative understandings of family, kinship, gender and belonging.