What exactly did the split over the Anglo-Irish Treaty of 1921 actually mean? We know it both established the independent Irish state and that Ireland would not be a fully sovereign republic and provided for the partition of Northern Ireland. The Treaty was ratified 64 votes to 57 by the Sinn Fein members of the Revolutionary Dail Eireann, splitting Sinn Fein irrevocably and leading to the Irish Civil War, a rupture that still defines the Irish political landscape a century on. Drawing together the work of a diverse range of scholars, who each re-examine this critical period in Irish political history from a variety of perspectives, The Anglo-Irish Treaty Debates addresses this vexed historical and political question for a new generation of readers in the ongoing Decade of Commemorations, to determine what caused the split and its consequences that are still felt today.