The Irish Party, the organization which represented the constitutional nationalist demand for home rule for almost fifty years in Westminster, was the most notable victim of the revolution in Ireland, c. 1916–23. Most of the last generation of Westminster-centred home rule MPs played little part in public life following the party’s electoral destruction in 1918. This article probes the political thought and actions of one of the most prominent constitutional nationalists who did seek to alter Ireland’s direction during the critical years of the war of independence. Stephen Gwynn was a guiding figure behind a number of initiatives to ‘ save ’ Ireland from the excesses of revolution. Gwynn established the Irish Centre Party in 1919, which later merged with the Irish Dominion League. From the end of 1919, Gwynn became a leading advocate of the Government of Ireland Bill, the legislation that partitioned the island. Revolutionary idealism – and, more concretely, violence – did much to render his reconciliatory efforts impotent. Gwynn’s experiences between 1919 and 1921 also, however, reveal the paralysing divisions within constitutional nationalism, which did much to demoralize moderate sentiment further.