This essay argues that nineteenth-century Americans interpreted Dante's Divine Comedy in terms of national and transnational discourses of federalism and republican nationalism, which helped introduce Dante to the United States and boosted the popularity and circulation of his works there. By the late 1840s, Dante--representing an Italy struggling to become an independent nation--was a useful, authoritative voice in political debates over national expansion and states' rights. His role expanded as these debates intensified. During the Civil War, Dante became an important discursive connection between republicanism, the new Italian nation-state, and the struggle to re-unify the American nation--a connection exemplified by Henry Wadsworth Longfellow's translation of the Comedy.