Book excerpt: Written as a narrative history of slavery within the United States, Unrequited Toil details how an institution that seemed to be disappearing at the end of the American Revolution rose to become the most contested and valuable economic interest in the nation by 1850. Calvin Schermerhorn charts changes in the family lives of enslaved Americans, exploring the broader processes of nation-building in the United States, growth and intensification of national and international markets, the institutionalization of chattel slavery, and the growing relevance of race in the politics and society of the republic. In chapters organized chronologically, Schermerhorn argues that American economic development relied upon African Americans' social reproduction while simultaneously destroying their intergenerational cultural continuity. He explores the personal narratives of enslaved people and develops themes such as politics, economics, labor, literature, rebellion, and social conditions.