For decades, historians of American Catholicism have examined how the Second Vatican Council (1962-1965) was received in the American context. While widely seen as an event that created progressive inroads in the Catholic Church, the conciliar documents tell a more complicated story. Developments in Catholic doctrine on ecumenical relations, religious liberty, and political participation became primary sources that, in the United States, were taken in multiple ideological directions by grassroots political activists. This project argues that the documents of the Second Vatican Council, received in the American context, helped foster a rapprochement between conservative Catholics and white Evangelical Protestants in the 1970s and 1980s. Using the council’s documents, American conservatives engaged with Catholics to create a broad, interdenominational conservative coalition that continues to influence American politics to this day.