Anglo-Irish War

Irish War of Independence
Seán Hogan's Flying column of the 3rd Tipperary Brigade during the war
Date 21 January 1919 – 11 July 1921 (2 years, 5 months, 2 weeks and 6 days) Location Ireland Result Ceasefire Anglo-Irish Treaty Creation of the Irish Free State
Belligerents
Irish Republic	United Kingdom
Commanders and leaders
Military commanders: Michael Collins Richard Mulcahy Cathal Brugha Political leaders: Éamon de Valera Arthur Griffith	Military commanders: Frederick Shaw Nevil Macready Henry Hugh Tudor Political leaders: David Lloyd George Lord French Lord FitzAlan Ian Macpherson Hamar Greenwood
Strength
Irish Republican Army ~15,000	British Army ~20,000 Royal Irish Constabulary 9,700 -Black and Tans 7,000 -Auxiliary Division 1,400 Ulster Special Constabulary 4,000
Casualties and losses
~550 dead	714 dead, comprising: -410 RIC dead -261 British Army dead -43 USC dead
~750 civilians dead Total dead: ~2,014

The Irish War of Independence (Irish: Cogadh na Saoirse) or Anglo-Irish War or the Tan War was a guerrilla war fought from 1919 to 1921 between the Irish Republican Army (IRA, the army of the Irish Republic) and the British security forces in Ireland. It was an escalation of the Irish revolutionary period into armed conflict.

In the December 1918 election, the Irish republican party Sinn Féin won a landslide victory in Ireland. On 21 January 1919 they formed a breakaway government (Dáil Éireann) and declared independence from Britain. Later that day, two members of the British-organized armed police force, the Royal Irish Constabulary (RIC), were shot dead in County Tipperary by IRA members acting on their own initiative. This is often seen as the beginning of the conflict. For much of 1919, IRA activity primarily involved capturing weapons and freeing republican prisoners. In September that year the British government outlawed the Dáil and Sinn Féin, and the conflict intensified thereafter. 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. The conflict as a result is often referred to as the Black and Tan War or simply the Tan War.

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