Irish Republican Army - Civil War

Civil War

The pro-treaty IRA soon became the nucleus of the new (regular) Irish National Army created by Collins and Richard Mulcahy. British pressure, and tensions between the pro- and anti-Treaty factions of the IRA, led to a bloody civil war, ending in the defeat of the anti-Treaty faction. On 24 May 1923, Frank Aiken, the (anti-treaty) IRA Chief-of-Staff, called a cease-fire. Many left political activity altogether, but a minority continued to insist that the new Irish Free State, created by the "illegitimate" Treaty, was an illegitimate state. They asserted that their "IRA Army Executive" was the real government of a still-existing Irish Republic. The IRA of the Civil War and subsequent organisations that have used the name claim lineage from that group, which is covered in full at Irish Republican Army (1922–1969).

For information on later organisations using the name Irish Republican Army, see the table below. For a genealogy of organisations using the name IRA after 1922, see List of organisations known as the Irish Republican Army.