The Irish War of Independence (1919-1921)

On the same morning that Dail Eireann, the separatist Irish parliament, met in Dublin and declared independence, IRA volunteers ambushed a Royal Irish Constabulary escort at Soloheadbeg in County Tipperary, killing two policemen. The ambush, unauthorized by IRA leadership, is conventionally treated as the opening act of the war. The new Dail and its Sinn Fein apparatus moved underground after being outlawed by Britain in September 1919.

Location: Soloheadbeg, Tipperary / Dublin, Ireland

Britain deployed the Black and Tans and the Auxiliary Division in 1920 to reinforce the overstretched Royal Irish Constabulary, whose barracks were being attacked and boycotted. Crown forces responded to IRA attacks with reprisals, including the sacking of Balbriggan in September 1920, in which parts of the town were burned and two villagers killed. The reprisals drew international criticism, particularly from the United States, and hardened Irish public opinion against British rule.

Location: Ireland

In a single day, Michael Collins's IRA squad killed 14 British intelligence officers at their Dublin homes in the morning. That afternoon, RIC and Auxiliary forces opened fire on the crowd at a Gaelic football match at Croke Park, killing 14 civilians. Later that night, three IRA suspects in custody at Dublin Castle were killed. The day became a defining symbol of the war's escalation on all sides.

Location: Dublin, Ireland

Days after Bloody Sunday, an IRA flying column under Tom Barry killed 17 Auxiliary policemen at Kilmichael in County Cork, demonstrating that elite British forces could be defeated in open combat. On 11 December 1920, in reprisal for an ambush at Dillon's Cross, Crown forces sacked Cork city center, burning City Hall and the Carnegie Library and destroying much of St Patrick's Street. The Cork fires, widely reported abroad, deepened international pressure on the British government.

Location: County Cork, Ireland

The British Parliament passed the Government of Ireland Act, creating two devolved home-rule jurisdictions: a six-county Northern Ireland and a Southern Ireland. The Act, designed to accommodate Ulster unionist insistence on remaining in the United Kingdom, confirmed the partition of the island while fighting continued. Northern Ireland came into being with its own parliament in 1921; Southern Ireland's institutions were never operational, as the war was resolved instead by the Anglo-Irish Treaty.

Location: London, United Kingdom

The IRA burned the Custom House, the seat of local government administration in Dublin, in its largest single operation of the war. The action destroyed a symbol of British administration, but over 100 IRA volunteers were captured, badly damaging the Dublin IRA's capacity. The loss pushed both sides toward negotiations, as neither could foresee a decisive military outcome.

Location: Dublin, Ireland

A truce agreed between the British government and the IRA came into effect on 11 July 1921, ending hostilities after roughly two and a half years and about 2,300 deaths, including some 900 civilians. Negotiations opened in London later that year between the British government and an Irish delegation led by Arthur Griffith and Michael Collins.

Location: Ireland

The Anglo-Irish Treaty established the Irish Free State as a self-governing dominion of the British Commonwealth, ended British rule over 26 counties, and confirmed the partition of the island. Its terms — an oath of allegiance, retention of British naval Treaty Ports, and the border with Northern Ireland — split Irish republicans. The Dail ratified the Treaty in January 1922, prompting the Irish Civil War between pro- and anti-Treaty forces that dominated Irish politics for a generation.

Location: London, United Kingdom