This thesis examines the executions policy undertaken by the pro-treatyite Provisional/Free State Government during the Irish Civil War (1922–23). Following the Irish War of Independence (1919–21) and subsequent Anglo-Irish Treaty Ireland‘s previously united nationalist movement fractured into opposing factions. The ensuing Civil War, fought between the Government and the anti-treatyite militants, known as the Irregulars, played an integral role in the development of the modern Irish State. Remarkably, this conflict has been marginalised in Irish revolutionary historiography. Similarly, the significance of the Government‘s official executions policy during the conflict has been further neglected and consigned to a footnote in existing works on the Civil War. Yet the execution of eighty-one fellow Irishmen and former comrades by the first independent Irish Government became one of the defining characteristics of the War. The proposition which underpins this study is that this executions policy had a significant impact on the dynamic of the Civil War, making it a far more ruthless and divisive affair. Moreover, it left an enduring legacy of bitterness in post-war Ireland, one which is still to be completely surmounted. In essence, this thesis presents an in-depth analysis of the effect of the executions policy on the character, course and outcome of the Irish Civil War.