Irish Civil War

The Irish Civil War, known in Irish as *Cogadh Cathartha na hÉireann*, lasted from 28 June 1922 to 24 May 1923. It broke out after the Irish War of Independence and coincided with the creation of the Irish Free State, a self-governing dominion within the British Empire rather than a fully independent republic. The fighting pitted the Provisional Government of Ireland against the Anti-Treaty IRA, with the central dispute being the Anglo-Irish Treaty. The Provisional Government—which became the Free State in December 1922—accepted the treaty’s terms. Their opponents, the anti-Treaty faction, viewed the agreement as a betrayal of the Irish Republic proclaimed during the 1916 Easter Rising. Many of those who fought on both sides had previously served together in the Irish Republican Army during the War of Independence, only to split once the conflict with Britain ended and treaty talks began. The pro-treaty National Army ultimately won the war. They secured Dublin by early July 1922, then pushed into anti-Treaty strongholds in the south and west, particularly the area known as the ‘Munster Republic’. By late August, all urban centres were under National Army control. A guerrilla phase followed for another ten months, until the IRA leadership ordered all units to “dump arms,” effectively ending the fighting. The National Army’s success was aided by substantial British-supplied weapons, including artillery and armoured cars. The war left Irish society deeply divided and bitter for generations. Today, the three largest political parties in Ireland trace their origins directly to the opposing sides: Fine Gael comes from the pro-Treaty supporters; Fianna Fáil was formed by Éamon de Valera from the bulk of anti-Treaty republicans; and Sinn Féin consists of the anti-Treaty republicans who refused to join any party that accepted partition. The Anglo-Irish Treaty was intended to end the 1919–1921 Irish War of Independence between the Irish Republic and the United Kingdom. It created a self-governing Irish state with its own army and police. The treaty also allowed Northern Ireland—the six north-eastern counties of Fermanagh, Antrim, Tyrone, Derry, Armagh, and Down, where Protestants formed the majority—to opt out of the new state and rejoin the United Kingdom, which it did immediately.