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.
Republic of Ireland
The state was created as the Irish Free State in 1922 as a result of the Anglo-Irish Treaty. It had the status of Dominion until 1937 when a new constitution was adopted, in which the state was named "Ireland" and effectively became a republic, with an elected non-executive president as head of state. It was officially declared a republic in 1949, following the Republic of Ireland Act 1948. Ireland became a member of the United Nations in December 1955. It joined the European Economic Community (EEC), the predecessor of the European Union, in 1973. The state had no formal relations with Northern Ireland for most of the twentieth century, but during the 1980s and 1990s the British and Irish governments worked with the Northern Ireland parties towards a resolution to "the Troubles". Since the signing of the Good Friday Agreement in 1998, the Irish government and Northern Ireland Executive have co-operated on a number of policy areas under the North-South Ministerial Council created by the Agreement.