Why has the religious right been more influential in the United States than in Canada? Traditional approaches to the study of social movements focus only on the life of the movement, from emergence to decline. Instead, I conduct a historical, comparative analysis on the premovement activities of evangelical Christian communities in these two countries from 1925–1975. Employing insights from historical institutionalism, I identify two critical junctures in the historical development of evangelical communities that suppressed the entrepreneurship and institution-building activities of Canadian evangelicals relative to those in the United States. I find that these divergences in institution building affected the size and strength of the institutional infrastructures—supportive organizations, networks, and resources—of the religious right movements in these countries. I argue that historical, comparative analysis in general, and historical institutionalism in particular, is useful to social movement scholarship's understanding of crossnational movement comparisons.