Unionism in the United Kingdom

In the United Kingdom, unionism is a political stance favouring the continued unity of England, Scotland, Wales and Northern Ireland as one sovereign state; the United Kingdom of Great Britain and Northern Ireland. Those who support the union are referred to as Unionists. Though not all unionists are nationalists, UK or British unionism is associated with British nationalism, which asserts that the British are a nation and promotes the cultural unity of the Britons, which may include people of English, Scottish, Welsh, Irish, Cornish, Jersey, Manx and Guernsey descent.

Since the late 20th century, differing views on the constitutional status of the countries within the UK have become a bigger issue in Scotland, Northern Ireland, and to a lesser extent in Wales. Sinn Fein and the Social Democratic and Labor Party, formed in 1905 and 1970, both function in Northern Ireland and advocate for Irish Unity. In 2010 Sinn Fein achieved a majority in the Northern Irish Legislative Assembly for the first time. The pro-independence Scottish National Party first became the governing party of the Scottish Parliament in 2007, and it won an outright majority of seats at the 2011 Scottish Parliament election. This led to a referendum on Scottish independence in 2014, where voters were asked: "Should Scotland be an independent country?" 44.7% of voters answered "Yes" and 55.3% answered "No", with a record voter turnout of 84.5%.

Formation of the Union

In 1542, the crowns of England and Ireland had been united through the creation of the Kingdom of Ireland under the Crown of Ireland Act 1542. Since the 12th century, the King of England had acted as Lord of Ireland, under papal overlordship.