The Irish Republican Army was not a single entity but a shifting, fractured movement.

Cultures · Published 29 September 2026 Swipe more like this →

In short: Following the 1921 Anglo-Irish Treaty, the IRA split into opposing factions, sparking a brutal civil war. Over the next four decades, the organization underwent radical transformations, swinging from Marxist-inspired social activism to Nazi-aligned espionage, all while struggling to define its legitimacy in a rapidly evolving Irish state.

The Irish Republican Army (IRA) originated from a 1922 split over the Anglo-Irish Treaty, which created the Irish Free State while leaving six northern counties within the United Kingdom. Anti-Treaty forces, labeled 'Irregulars' by the government, viewed themselves as the legitimate army of the 1916 Republic. This led to an eleven-month civil war characterized by bitter reprisals, including the execution of 77 anti-Treaty prisoners by the Free State and the retaliatory killing of parliamentarians.

Post-Civil War, the organization’s identity became fluid. By the 1930s, under leaders like Moss Twomey, the IRA flirted with left-wing politics and even maintained a secret espionage pact with the Soviet Union, trading British military intelligence for funding. Conversely, by 1938, leadership under Seán Russell shifted the group toward the right, leading to contact with Nazi Germany and the 1939 S-Plan bombing campaign in Britain. These ideological pivots often alienated the public, as the IRA’s influence waned following the introduction of a new Irish constitution in 1937.

The organization’s final decades were marked by internal instability. In the 1960s, leadership under Cathal Goulding pushed a Marxist, class-based agenda, aiming to end the policy of abstentionism from parliament. This shift, coupled with the IRA’s perceived failure to defend Catholics during the 1969 Northern Ireland riots, triggered a definitive split. The resulting divide between the Official and Provisional IRA marked the end of this specific iteration of the organization, leaving behind a legacy of complex, often contradictory, paramilitary history.

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