Res Publica and the Roman Republic tells the story of an idea - res publica - and shows us what it meant and was made to mean in the particular historical context of the late Roman Republic. Since the term was politically ubiquitous, often used emotively, and as a consequence is hard to define, the temptation to take res publica as a universally understood and relatively uncontroversial given is rarely resisted. A close look at how res publica was perceived and manipulated, however, brings into focus not just the political crises of the late Republic but also the various attempts to clean up these crises through dubiously legal (and often outright illegal) emergency measures. Although this book is at root a philological study of a political concept, it aims to make a historical point about a politically turbulent period by addressing three key questions: What did it mean for Republican politicians to appeal to the res publica? What did the increasing tendency to do so reveal about the dangerous fragmentation of political legitimacy? How did these pressures transform res publica as a concept? Through a detailed examination of res publica as it appears in the ancient historians, orators, poets, commentaries and letters, inscriptions, and historical episodes of the late Republic and early Principate, this book demonstrates how the rhetoric surrounding res publica mirrored the changes in the Roman political landscape towards the end of the Republic.