The Irish Free State offensive of July–September 1922 was the decisive military stroke of the Irish Civil War. It was carried out by the National Army of the newly created Irish Free State against anti-treaty strongholds in the south and southwest of Ireland.
At the beginning of the Civil War in June 1922, the Irish Free State government, composed of the leadership faction who had accepted the Anglo-Irish Treaty, held the capital city of Dublin, where its armed forces were concentrated and some other areas of the midlands and north. The new National Army was composed of those units of the Irish Republican Army loyal to them, plus recent recruits, but was, at the start of the war, still relatively small and poorly armed.
Much of the rest of the country, particularly the south and west, was outside of its control and in the hands of the anti-Treaty elements of the IRA, who did not accept the legitimacy of the new state and who asserted that the Irish Republic, created in 1919, was the continuing legitimate all-island state.