Irish War of Independence

Irish War of Independence, (1919–21), conflict that pitted Irish nationalists (republicans), who were pursuing independence from the United Kingdom for Ireland, against British security forces and Irish loyalists (unionists), who sought to preserve Ireland’s union with Great Britain. The war concluded with the Anglo-Irish Treaty of December 6, 1921, which established 26 counties in the south of Ireland as the Irish Free State, with dominion status within the British Empire, while granting “Home Rule” to six predominantly Protestant counties in the north (Ulster), which remained a self-governing part of the United Kingdom. Dissension among nationalists over the agreement resulted in the Irish civil war (1922–23).

Pursuit of Home Rule

The pursuit of autonomy for Ireland within the United Kingdom escalated in the final decades of the 19th century. After the Home Rule bills of 1886 and 1893 were rejected by Parliament, a third such bill was enacted in September 1914, though it failed to satisfy many unionists and nationalists. Nevertheless, unionists had formed a paramilitary army, the Ulster Volunteer Force (UVF), to try to block Home Rule, while nationalists created their own militia, the Irish Volunteers, as a counterforce. The mounting pressure was reduced when attention shifted to support for the British war effort at the outbreak of World War I. Moreover, because of the onset of the war, the Home Rule Act (formally the Government of Ireland Act, 1914) was immediately suspended for 12 months. Because of subsequent developments, its implementation would later be postponed again and ultimately would never occur.

The Easter Rising

As World War I dragged on, support increased for an extreme nationalist faction of the Irish Volunteers that opposed involvement in the British war effort. The Irish Republican Brotherhood (IRB), a revolutionary society that held sway over this faction, had been planning an insurrection against British rule since 1914, and on Easter Monday, April 24, 1916, a revolt led by the IRB broke out in Dublin involving about 1,000 men and women. A provisional Irish republican government was proclaimed, and the Dublin General Post Office and other strategic points in Dublin’s city centre were seized. After about a week of street fighting, the rebellion was squelched, and Tom Clarke, Patrick Pearse, and other republican leaders were forced to surrender. Their executions made martyrs of them and sparked an explosion of anti-British outrage, which only increased when it appeared that conscription might be introduced in Ireland.

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The 1918 election

The Easter Rising and the groundswell of support for republicanism that it had catalyzed reversed the political fortunes of John Redmond, who had engineered passage of the 1914 Home Rule Act and promised full Irish support to the Allies in World War I. The general election of 1918 resulted in the defeat and virtual extinction of Redmond’s Irish Parliamentary Party. On the other hand, Sinn Féin—the Irish nationalist party, which had been of little importance before the Easter Rising but thereafter became the rallying point for extreme nationalist sentiment—won 73 of the 105 Irish seats in the British Parliament. Led by Eamon de Valera, the chief survivor of the uprising’s leadership, Sinn Féin MPs refused to take their seats in the Westminster Parliament. Instead, they met in Dublin in January 1919 as the Dáil Éireann (“Irish Assembly”), declaring themselves the parliament of an Irish republic and setting up a provisional government in opposition to Ireland’s British administration.

The Irish Republican Army

In the meantime, the Irish Republican Army (IRA) was created in 1919 as a successor to the Irish Volunteers to use armed force to resist British rule in Ireland. Thus began the Irish War of Independence, in which the IRA, under the leadership of Michael Collins, employed guerrilla tactics, mounting widespread ambushes, raids, and attacks on police barracks. The British forces responded with ruthless reprisals.

Black and Tans

When a large proportion of the Irish police resigned, the Royal Irish Constabulary (RIC) was filled with British recruits, most of whom were jobless former soldiers. They became known as Black and Tans because of the dark police tunics and khaki military trousers they were issued as makeshift uniforms.

Bloody Sunday

In seeking to combat the terrorism of the IRA, the Black and Tans engaged in brutal counteractions. Most notably, after the IRA killed at least 14 individuals (most of whom were English and were suspected of being intelligence agents) on November 21, 1920, the Black and Tans took revenge the same day by attacking spectators at a Gaelic football match in Croke Park, Dublin, killing 14 and wounding 60. The event became known as Bloody Sunday.

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Death toll and truce

By the end of 1920, about 500 people had been killed in the war. In the first half of 1921, approximately another 1,000 persons had died as a result of the conflict. Meanwhile, about 6,000 republicans were put in prison. By the summer of 1921—though the IRA was becoming short of manpower, weapons, and ammunition—no immediate end to the war was in sight. Nonetheless, a truce was reached on July 11, 1921, and talks on a political settlement began.

The Anglo-Irish Treaty

In October 1921 Collins and Arthur Griffith were sent to London by de Valera to conduct negotiations. The resulting Anglo-Irish Treaty was signed on December 6, 1921, by Collins (as well as Griffith), who believed that it was the best that could be obtained for Ireland at the time. The settlement established two new political entities: the Irish Free State, which comprised 26 counties and was granted dominion status within the British Empire (requiring an oath of allegiance to the British crown that Collins knew would be unacceptable to de Valera and other republican leaders); and Northern Ireland, made up of six counties that were sometimes called the province of Ulster, which remained part of the United Kingdom.

The path to the Irish Civil War

Collins’s persuasiveness helped win acceptance for the treaty by a small majority in the Dáil. But the terms of the treaty did indeed prove unacceptable to a substantial number of Sinn Féin members and split the party into two factions, one (under Collins’s leadership) supporting the treaty and the other (under de Valera) opposing it. The former group became the core of the official Irish Free State Army, and the latter group, known as “Irregulars,” began to organize armed resistance against the new independent government. The two sides fought against each other in the ensuing Irish civil war (1922–23), which ended in the defeat of the anti-treaty forces.