From its inception, antievolution activism has been aimed not only at the natural sciences but also, and almost as often, at the social sciences. Although almost entirely overlooked by scholars, this activism played a significant part in the development of American social science in the early twentieth century. Analyzing public writings and private papers of antievolution activists, academic social scientists, and university officials from the 1920s, this essay recalls this forgotten history, showing how antievolution activism contributed to the abandonment of evolutionary theory and the adoption of a set of secular, scientific, and professional characteristics that have come to define much of modern social science.