Partition of Ireland
Beginning on 21 January 1919 with the Soloheadbeg ambush, through the Irish War of Independence, Irish republicans attempted to bring about the secession of Ireland from the United Kingdom of Great Britain and Ireland. Meanwhile, Irish unionistsmost of whom lived in the northeast of the islandwere just as determined to maintain the Union. The British Government, committed to implementing Home Rule, set up a cabinet committee under the chairmanship of southern unionist Walter Long. The Long Committee recommended the establishment of two devolved administrations, dividing the island into two territories: Northern Ireland and Southern Ireland. This was implemented as the Government of Ireland Act 1920. The act entered into force as a "" on 3 May 1921 and provided that Northern Ireland would consist of the six northeastern counties, while the remainder of the island would form Southern Ireland. It was intended that each jurisdiction would be granted home rule but remain within the United Kingdom. The government of Southern Ireland never functioned: the war for independence continued until the two sides agreed a truce in July 1921, ending with the Anglo-Irish Treaty on 6 December 1921.
History of Ireland
The period 1916–1921 was marked by political violence and upheaval, ending in the partition of Ireland and independence for 26 of its 32 counties. A failed militant attempt was made to gain separate independence for Ireland with the 1916 Easter Rising, an insurrection in Dublin. Though support for the insurgents was small, the violence used in its suppression led to a swing in support of the rebels. In addition, the unprecedented threat of Irishmen being conscripted to the British Army in 1918 (for service on the Western Front as a result of the German Spring Offensive) accelerated this change. In the December 1918 elections Sinn Féin, the party of the rebels, won three-quarters of all seats in Ireland, twenty-seven MPs of which assembled in Dublin on 21 January 1919 to form a 32-county Irish Republic Parliament, the first Dáil Éireann unilaterally declaring sovereignty over the entire island.
Unwilling to negotiate any understanding with Britain short of complete independence, the Irish Republican Army, the army of the newly declared Irish Republic, waged a guerilla war (the Irish War of Independence) from 1919 to 1921. In the course of the fighting and amid much acrimony, the Fourth Government of Ireland Act 1920 implemented Home Rule while separating the island into what the British government's Act termed "Northern Ireland" and "Southern Ireland". In July 1921 the Irish and British governments agreed to a truce that halted the war. In December 1921 representatives of both governments signed an Anglo-Irish Treaty. The Irish delegation was led by Arthur Griffith and Michael Collins. This abolished the Irish Republic and created the Irish Free State, a self-governing Dominion of the Commonwealth of Nations in the manner of Canada and Australia. Under the Treaty, Northern Ireland could opt out of the Free State and stay within the United Kingdom: it promptly did so. In 1922 both parliaments ratified the Treaty, formalising independence for the 26-county Irish Free State (which renamed itself "Ireland" in 1937, and declared itself a republic in 1949); while the 6-county Northern Ireland, gaining Home Rule for itself, remained part of the United Kingdom. For most of the next 75 years, each territory was strongly aligned to either Catholic or Protestant ideologies, although this was more marked in the six counties of Northern Ireland.