Unionism in Ireland

Unionism in Ireland is an ideology which favours the continuation of some form of political union between the islands of Ireland and Great Britain. Since the separation of the Irish Free State from the United Kingdom as a Dominion and its subsequent emergence as an independent state, unionism in Ireland has focused primarily on maintaining and preserving the place of Northern Ireland within the United Kingdom.

The political relationship between England and Ireland dates from the 12th century Norman invasion. In the Act of Union 1800, the United Kingdom of Great Britain and Ireland was created. In 1922, twenty-six counties of Ireland gained autonomy from the U.K. as a U.K. Dominion as the Irish Free State; in 1949, this Dominion became a Republic and ipso facto, left the Commonwealth. The remaining six counties constituted the territory of Northern Ireland, which has remained part of what in 1927 was renamed the "United Kingdom of Great Britain and Northern Ireland". Today, active unionism is overwhelmingly an Northern Ireland issue, concerned primarily with the governance of and relationship between Northern Ireland and Great Britain. In the Irish Republic today, there is scant support for unionists who would advocate the state rejoining the UK, and only a substantial minority who would politically support Irish reunification.

Unionism and its opposing ideology, Irish nationalism, are associated with particular ethnic and/or religious communities. Most, but not all, unionists are of one of various Protestant backgrounds. Nationalists are mostly of a Catholic background. However, these are generalisations, because there are both Protestant nationalists and Catholic unionists, as well as more recent immigrants, and their descendants, some of whom are neither Catholic nor Protestant.