The Vietnam War and its polarizing era challenged, splintered, and changed The National Council of the Churches of Christ in the U.S.A. (NCC), which was motivated by its ecumenical Christian vision to oppose that war and unify people. The NCC’s efforts on the war exposed its strengths and imploded its weaknesses in ways instructive for religious institutions that bring their faith into politics. Embattled Ecumenism explores the ecumenical vision, anti-Vietnam War efforts, and legacy of the NCC. Gill’s monumental study serves as a window into the mainline Protestant manner of engaging political issues at a unique time of national crisis and religious transformation. In vibrant prose, Gill illuminates an ecumenical institution, vision, and movement that has been largely misrepresented by the religious right, dismissed by the secular left, misunderstood by laity, and ignored by scholars outside of ecumenical circles. At a time when the majority of scholarly work is committed to looking at the religious right, Gill’s groundbreaking study of the Protestant Left is a welcome addition. Embattled Ecumenism will appeal to scholars of U.S. religion, politics, and culture, as well as historians of evangelicalism and general readers interested in U.S. history and religion.