is a sociohistorical tour de force that examines the entwined formation of racial theory and sexual constructs within settler colonialism in the United States and Australia from the Age of Revolution to the Great Depression. Gregory D. Smithers historicizes the dissemination and application of scientific and social-scientific ideas within the process of nation building in two countries with large Indigenous populations and shows how intellectual constructs of race and sexuality were mobilized to subdue Aboriginal peoples. Building on the comparative settler-colonial and imperial histories that appeared after the book’s original publication, this completely revised edition includes two new chapters. In this singular contribution to the study of transnational and comparative settler colonialism, Smithers expands on recent scholarship to illuminate both the subject of the scientific study of race and sexuality and the national and interrelated histories of the United States and Australia. is an associate professor of history at Virginia Commonwealth University. He is the author of several books, including and is the coeditor of (Nebraska, 2014).