Although engaged in questioning the precepts of the eugenics movement from its inception, Catholic leaders’ interest in the movement reached its apogee in the late 1920s, when the twin issues of compulsory sterilization and birth control came to dominate the debate over eugenics. Through an examination of the work of Rev. John A. Ryan and Rev. John M. Cooper, two Catholic leaders who were once members of the American Eugenics Society, this chapter describes the intellectual journey of the Catholics who eventually became the eugenics movement’s most fervent opponents. It reviews Catholic debate about eugenic sterilization, the reaction to Margaret Sanger’s fledgling birth control movement, and the lay and clerical reaction to Pope Pius XI’s encyclical Casti Connubi.
Keywords: Catholics, John Augustine Ryan, John Montgomery Cooper, American Eugenics Society, Leon F. Whitney, natural law, sterilization, birth control, Margaret Sanger, Casti Connubi,