Using the Developmental Niche for Emergent Participatory Citizenship (Torney-Purta and Amadeo, 2011) as a framework, we examined differences between immigrant and native-born youth's civic knowledge and support for women's rights in Sweden and the United States, and explored whether experiences with peers and parents, and in formal and informal educational contexts, could account for such differences. Using data from the IEA Civic Education Study of 1999, we found that immigrants had lower civic knowledge and less support for women's rights than their native-born peers in both countries. Differences in civic knowledge were partially explained in both countries by the lower likelihood of immigrants speaking the tested language at home, and remaining gaps were moderated by differences in the association of school activities with knowledge between the two groups. Gaps in support for women's rights were partially explained by differences in language spoken at home (a possible proxy for cultural dissimilarity) in the United States, but not in Sweden. Experiences in various social or educational contexts, including perceptions of