Why the Irish Republican Army is not one group but a century of splits

History · Published 30 September 2026 Swipe more like this →

In short: The name Irish Republican Army has been claimed by various militant groups for over a century. From its origins as the revolutionary army of the Irish Republic to the fractured paramilitary organizations of the modern era, the IRA is defined less by a single identity than by constant, internal division.

The original Irish Republican Army, or 'old IRA', emerged in 1919 from the Irish Volunteers and the Irish Citizen Army. Recognized by the Dáil Éireann as the legitimate military force of the revolutionary Irish Republic, it fought against British rule during the Irish War of Independence. However, the organization's unity proved fragile. Following the Anglo-Irish Treaty of 1921, the force fractured into pro-Treaty National Army regulars and anti-Treaty republicans, leading to the Irish Civil War of 1922–1923.

This pattern of fragmentation became a defining feature of the movement. Playwright Brendan Behan famously remarked that the first item on any Irish organization's agenda was 'the split'. After the civil war, the anti-Treaty IRA persisted for over four decades, refusing to recognize the legitimacy of the Irish Free State or Northern Ireland. By 1969, the organization underwent a major schism, separating into the Marxist-oriented Official IRA and the Provisional IRA. The latter became a central participant in the Troubles, though it too eventually faced internal breakaways.

In the decades that followed, further splinter groups emerged, including the Continuity IRA in 1986 and the Real IRA in 1997, both driven by opposition to changing political strategies or the Northern Ireland peace process. By 2012, the New IRA was formed through a merger of the Real IRA and other republican factions. Each of these modern iterations has insisted on its status as the sole, legitimate successor to the original 1919 organization, often claiming the mantle of the mainstream IRA to justify their continued existence and militant activities.

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