How suburbanization was a crucial catalyst for reforms in the Catholic Church.   The 1960s in America were a time of revolt against the stifling conformism embodied in the sprawling, uniform suburbs of the 1950s. Typically, the reforms of the Catholic Church’s Second Vatican Council, which aimed to make the Church more modern and accessible, are seen as one result of that broader cultural liberalization. Yet in Crabgrass Catholicism, Stephen M. Koeth demonstrates that the liberalization of the Church was instead the product of the mass suburbanization that began some fifteen years earlier. Koeth argues that postwar suburbanization revolutionized the Catholic parish, the relationship between clergy and laity, conceptions of parochial education, and Catholic participation in US politics, and thereby was a significant factor in the religious disaffiliation that only accelerated in subsequent decades. A novel exploration of the role of Catholics in postwar suburbanization, Crabgrass Catholicism will be of particular interest to urban historians, scholars of American Catholicism and religious studies, and Catholic clergy and laity.