Those who defended and crafted republics in Britain, America, and Europe drew upon a vast range of languages and conceptual vocabularies to define republicanism, forge political unions, and warn of the dangers of excess and fanaticism. This panel offers a comparative perspective of the long republican tradition, emphasizing the vigorous and energetic analogies and metaphors that writers adopted in the early modern and modern period to defend republicanism as a political system against monarchism, fanaticism, or corruption. As each paper demonstrates, the “languages” and discourses which shaped republicanism included broad influences past and present; whereas early modern writers in Britain and America adopted medical and cosmic ideas of cooperation and citizenship to champion republican ideas of liberty, modern writers seeking to combat fascism revived republican languages previously mired in debates over commerce, enlightenment, and war. Through this range of case studies, the panel shows how a classical mode of thinking – republicanism – became conceptualized and communicated in new political contexts.