The Easter Rising in 1916 is a momentum of consequence in Irish history, deeply related to national self-definition. In The Plough and the Stars, written in 1926, 10 years after the event, O'Casey attempts to demytholize the historical event which has been glorified as the nationalistic heroic one, and to make it as a war game:'Patriot Game'. In a word, O'Casey's The Plough and the Stars is an iconoclastic reconception of ‘Easter 1916’. The uniqueness of O'Casey's portrayal of the Easter Rising in The Plough and the Stars is that the historical event is seen through the window, being placed outside the tenement, with the historical figures and heroes staying outside and with the historical speech being heard off the stage by the shadow figure. This paper aims to explore how O'Casey, a socialist before a nationalist, refashions the past in his dramatization of the very significant historical fact in his mother land, Ireland. Introduction part contains discussion concerning the significance of the Easter Rising in Irish history as well as the history of the world, and the critical attitude toward the play. Part Ⅱ examines O'Casey's techniques which place the public cause against the private value, focusing on Clitheroe's family, where the role of the patriot is chosen and the role of the husband is abandoned. From the very first beginning, the fact that the cause for the nation is posed against the cause for the family, sacrificing each other, and that these two can not go together toward one direction and should be chosen as an alternative, shows the ultimately destructive end of the 'Patriot Game', causing death and destruction of both individuals and the nation. In joining the patriotic project, Clitheroe's vanity for glory, his ambition to be a hero, and theatricality are also discussed. Besides, Nora's role as a critic of the war and the Easter Rising is examined. Part Ⅲ examines the gap between the heroes and the people by focusing on the shadow figure's heroic speeches and the responses of Covey, Bessie, and Rosie as well as those of the participants of the Easter Rising. While the history is happening outside the window, Covey as a socialist, Bessie as the representative of Irish mothers who lose their sons in a battlefield, and Rosie as one of the poor Irish people respond respectively to the historical moment. The several aspects of Ireland are seen through these people in the pub: a socialist, a nationalist, a Catholic, a Protestant, a prostitute and heroic participants. Part Ⅳ focuses on the results of the Easter Rising and discusses the significance of the revolution in a nation and individual's life. The cause and aims of the patriotic game do not go in the direction of the participants' original intentions, engendering no more than destructive results such as Clitheroe's death, Nora's madness, her baby's death, Mollser's death, Bessie's abrupt death and the plundering of the Irish people and their being shot by the Irish soldiers. Ireland becomes the land of the death, which strongly provokes a question: the revolution for whom? For whom do they fight? To O'Casey, any historic event is no more than a war game and a 'Patriot Game' without having deep concerns to the needs of the poor orking class people, whatever great causes and '-isms' for the nation and for the whole people they have. And the Easter Rising is no exception. To O'Casey, the Easter Rising is no more than 'a tragic and premature lost opportunity': a history outside the window.