What undergirds the association between religious and political conservatism and “group-serving pronatalism”; that is, support for childbearing to advance social or political goals rather than for personal fulfillment? Although recent research suggests that Christian nationalism—reflecting a desire to formally privilege conservative Christian values and identity—strongly accounts for the link, previous studies have not inquired about specific group-serving reasons to have children. Analyses of nationally representative data affirm Christian nationalism (measured in two ways) as the strongest predictor of support for group-serving pronatalism; specifically, support for having children to reverse the nation’s declining fertility, perpetuate one’s religious or racial heritage, and secure influence for one’s political group. These associations are weakly or inconsistently moderated by indicators of traditionalism, conservatism, and race. Findings affirm support for having children to advance national, religious, racial, or political goals corresponds strongly with a desire to privilege a Christian national identity and social order.