Catholic Social Activism asks a number of questions regarding Catholic faith and politics: How have American laypeople responded to contentious political moments, including times of war, severe economic trouble, human rights abuses, environmental degradation, and encounters with refugees fleeing these problems? How have they interpreted official church documents and translated them into progressive action for immigrant rights and women’s rights? And how have their movements influenced religious leaders and Catholic Social Teachings? Drawing upon in-depth interviews with activists, archival documents, and secondary resources, the book captures the lived religious experiences of progressive American Catholic activists. It explores how their faith has led them to innovative and sometimes controversial engagement in various movements, including the Catholic Worker, the United Farm Workers, peace movements, Catholic feminism, the Central America solidarity movement, the Sanctuary movement, and the environmental movement. The book argues that these activists have shaped the landscape of American Catholicism and pressured the Catholic hierarchy from below, often prompting them to take a stand and articulate the theological bases for social justice. In compelling prose, the book uncovers the progressive and sometimes radical history of American Catholics, whose stories have for too long remained on the margins of public awareness.