Irish War of Independence
Guerrilla war between IRA and British forces, 1919–1921.
The Irish War of Independence, also called the Anglo-Irish War or, in Irish, *Cogadh na Saoirse*, was a guerrilla conflict that took place in Ireland between 1919 and 1921. It was fought between the Irish Republican Army (IRA), which served as the military of the self-declared Irish Republic, and British forces—namely the British Army, the Royal Irish Constabulary (RIC), and the RIC’s paramilitary auxiliaries, the Auxiliaries and the Ulster Special Constabulary (USC). This war was one chapter in Ireland’s broader revolutionary period.
The roots of the conflict stretch back to the Easter Rising of April 1916, when Irish republicans rose up against British rule and proclaimed an independent Irish Republic. Though the rising was crushed within a week, both the event itself and the harsh British response shifted public opinion in Ireland toward supporting independence. In the general election of 1918, the republican party Sinn Féin won a sweeping victory. On 21 January 1919, its elected members formed a breakaway government called Dáil Éireann and declared Irish independence. That same day, IRA volunteers acting without official orders killed two RIC officers in an ambush at Soloheadbeg. The conflict did not erupt all at once; for most of 1919, the IRA focused on seizing weapons and freeing republican prisoners, while the Dáil worked to build the structures of a new state. In September 1919, the British government outlawed the Dáil across Ireland and declared Sinn Féin illegal in County Cork, which escalated the fighting. The IRA then began ambushing RIC and British Army patrols, attacking their barracks, and forcing isolated outposts to close. To reinforce the RIC, Britain recruited the Black and Tans and the Auxiliaries from its own population. These units became infamous for their lack of discipline and for carrying out reprisal attacks on civilians—some of which were officially sanctioned. Because of this, the conflict is sometimes called the “Black and Tan War.” The struggle also included acts of civil disobedience, such as Irish railway workers refusing to transport British troops or military supplies.
By mid-1920, republicans had gained control of most county councils, and British authority had collapsed across much of southern and western Ireland, prompting the British government to introduce emergency powers. Around 300 people had died by late 1920, b
- started
- 1919
- ended
- 1921
- field
- Guerrilla war
- nationality
- Irish
- known_for
- Conflict between IRA and British forces leading to Irish independence
Lore & Background
The conflict developed gradually after the 1918 general election, in which republican party Sinn Féin won a landslide victory in Ireland. On 21 January 1919, they formed a breakaway government (Dáil Éireann) and declared Irish independence. That day, two RIC officers were killed in the Soloheadbeg ambush by IRA volunteers acting on their own initiative. For most of 1919, IRA activity involved capturing weaponry and freeing republican prisoners, while the Dáil set about building a state. In September 1919, the British government outlawed the Dáil throughout Ireland, and the conflict intensified. The IRA began ambushing RIC and British Army patrols, attacking their barracks and forcing isolated barracks to be abandoned. The British government bolstered the RIC with recruits from Britain—the Black and Tans and Auxiliaries—who became notorious for ill-discipline and reprisal attacks on civilians, some of which were authorised by the British government. The conflict also involved civil disobedience, notably the refusal of Irish railwaymen to transport British forces or military supplies.
Reader's Guide
The Irish War of Independence was a pivotal conflict that ended British rule in most of Ireland and led to the establishment of the Irish Free State as a self-governing Dominion in 1922, while Northern Ireland remained within the United Kingdom. The war saw escalating violence, including the Bloody Sunday assassinations and the Kilmichael Ambush, and resulted in over 1,000 deaths and 4,500 republicans interned. The conflict also had a sectarian aspect in north-east Ulster, where almost 500 were killed, most of them Catholics. The ceasefire began on 11 July 1921, and the subsequent Anglo-Irish Treaty ended British rule in most of Ireland. Disagreement over the treaty led to the Irish Civil War. The Irish Free State awarded 62,868 medals for service during the War of Independence, of which 15,224 were issued to IRA fighters of the flying columns.
Did You Know?
- The conflict is sometimes called the 'Black and Tan War' due to the ill-discipline of British-recruited Black and Tans and Auxiliaries.
- On Bloody Sunday, 21 November 1920, fourteen British intelligence operatives were assassinated, and later that day RIC fired on a crowd at Croke Park, killing fourteen civilians.
- The IRA killed seventeen Auxiliaries in the Kilmichael Ambush in County Cork a week after Bloody Sunday.
- The conflict in Belfast saw almost 500 killed, most of them Catholics, amid sectarian violence.
More in European Religious And Political Conflicts 1-19
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