1. United Kingdom/Ireland (1902-1922)

Pre-Crisis Phase (October 1, 1902-April 23, 1916): Irish nationalists led by Arthur Griffith established Sinn Fein in opposition to the British government in October 1902. The Irish Volunteers (IV) was established by Eoin MacNeill in support of Irish independence in November 1913. The British parliament approved a Home Rule Act for Ireland in September 1914. Germany agreed to provide military assistance (weapons and ammunition) to Irish nationalists in March 1916, but the military assistance was intercepted by the British before it could get to the Irish nationalists. Sir Roger David Casement, an Irish nationalist leader, was smuggled into Ireland from a German submarine on April 20, 1916.

Crisis Phase (April 24, 1916-July 11, 1917): Some 1,600 Irish nationalists led by Patrick Pearse, James Connolly, and Sir Roger Casement rebelled against the British government in Dublin on April 24, 1916, and the British government proclaimed martial law in Ireland on April 27, 1916. British troops suppressed the rebellion on April 29, 1916. Some 250 Irish civilians, 64 Irish nationalists, and 132 government soldiers were killed during the Easter Rebellion. Some 3,000 Irish nationalists were arrested for their involvement in the rebellion. Fifteen Irish nationalists, including Patrick Pearse, James Connolly, and Sir Roger Casement were executed for their involvement in the rebellion on August 3, 1916. On June 15, 1917, the British government granted amnesty to hundreds of Irish nationalists imprisoned for their involvement in the Eastern Rebellion. Eamon de Valera, leader of Sinn Fein, was released from prison on July 11, 1917. Some 500 individuals were killed during the crisis.

Post-Crisis Phase (July 12, 1917-January 20, 1919): Eamon de Valera was elected president of the Irish Republic by members of the Sinn Fein on October 27, 1917. Eamon de Valera was arrested by British police on May 18, 1918. Parliamentary elections were held on November 1918, and Sinn Fein won 73 seats out of 106 seats allocated to Ireland in the British House of Commons. The Ulster Unionists (UU) won 26 seats in the British House of Commons.

Crisis Phase (January 21, 1919-November 25, 1919): The Sinn Fein members of the British parliament established an Irish parliament (Dail Eireann), and declared Ireland’s independence from Britain on January 21, 1919. Irish nationalists killed two government policemen near Soloheadbeg on January 21, 1919. Eamon de Valera escaped from prison on February 3, 1919, and he took refuge in the US. The Irish Volunteers formally became the Irish Republican Army (IRA) in August 1919. The Irish parliament was declared illegal by the British government on September 11, 1919.

Conflict Phase (November 26, 1919-July 11, 1921): Members of the IRA, military wing of Sinn Fein, rebelled against the British government beginning on November 26, 1919. IRA rebels killed a total of 18 government policemen in 1919. The British government deployed the Royal Irish Constabulary (RIC), also known as Black and Tans, in Northern Ireland on May 15, 1920. IRA rebels killed fourteen government personnel in Dublin, and RIC personnel killed 12 Irish civilians in Dublin on November 21, 1920 (Bloody Sunday). IRA rebels led by Tom Barry and RIC personnel clashed near Kilmichael on November 28, 1920, resulting in the deaths of 17 RIC personnel and three IRA rebels. The Vatican, represented by Archbishop Clune of Australia, attempted to mediate negotiations between British and Irish representatives between December 1920 and January 1921. The British parliament approved the Government of Ireland Act on December 23, 1920, which provided for separate parliaments for Northern Ireland and Southern Ireland and the establishment of a Council for Ireland. IRA rebels killed a total of 176 government policemen and 54 government soldiers in 1920. IRA rebels led by Tom Barry and government troops clashed near Crossberry on March 19, 1921, resulting in the deaths of 39 government soldiers and three IRA rebels. Parliamentary elections were held on May 13-24, 1921, and Sinn Fein won 124 out of 128 seats in the parliament. The IRA agreed to a cessation of military hostilities on July 10, 1921, and the ceasefire went into effect on July 11, 1921. IRA rebels killed 228 government policemen and 96 government soldiers in 1921. Some 425 government policemen, 150 government soldiers, 650 Irish nationalists, and 200 Irish civilians were killed during the conflict.

Post-Conflict Phase (July 12, 1921-January 15, 1922): British and Irish representatives held negotiations between July 14 and December 6, 1921. British and Irish representatives signed a peace treaty on December 6, 1921, which provided for the dominion status within the British Commonwealth for all but six Irish counties in northern Ireland. The Dail Eireann formally ratified the peace treaty on January 15, 1922.

[Sources: Buckland 1972; Clodfelter, 1992, 588, 589-590; Curran 1980; Gilbert, 1997, 402-404; Jackson, 1999, 142-274; Jessup, 1998, 670; Kostick 1996; Langer, 1972, 983-984; Smith 2000.]