Irish republicanism is the political movement for the unity and independence of Ireland under a republic. Irish republicans view British rule in any part of Ireland as inherently illegitimate. An ideology since the 17th century, various methods have been employed to achieve the republic, including rebellions and paramilitary campaigns. Although the makeup of republicanism has been multidenominational, its relation to catholicism increasingly became central.

The Good Friday Agreement (GFA) or Belfast Agreement is a pair of agreements signed on 10 April, Good Friday, 1998, that ended most of the violence of the Troubles, an ethno-nationalist conflict in Northern Ireland since the late 1960s. It was a major development in the Northern Ireland peace process of the 1990s. It is made up of the Multi-Party Agreement between most of Northern Ireland's political parties, and the British–Irish Agreement between the British and Irish governments. Northern Ireland's present devolved system of government is based on the agreement.