Unionism in the United Kingdom  Unionism in the United Kingdom, also referred to as British unionism, is a political ideology favouring the continued unity of England, Wales, Scotland 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"". In the lead up to the American War of Independence in the second half of the 18th century, there existed British loyalists and colonial rebels (Whigs or Patriots). None of the Loyalists wanted separation. Not even a majority amongst the Rebels necessarily desired to be separate from Great Britain. Later, towards the end of the 19th century, Irish Unionism was by and large a reaction to an increase in separatist Irish nationalist agitation or self governance in Home Rule. Most of Ireland became separated from the UK in the 1920s. In Northern Ireland the polarised constitutional ideologies of republicans and loyalists has led to violent conflict, known as the Troubles. Since the late 20th century differing views on the constitutional status of the countries within the UK has become a bigger issue in Scotland and Wales. Following the Scottish National Party's victory in Scotland's 2011 election, a referendum on Scottish independence took place on 18 September 2014: the result supported remaining within the United Kingdom, winning the vote by 55.3% No to 44.7% Yes to the question "Should Scotland be an independent country?". The Kingdom of Great Britain was formed on 1 May 1707 through the Acts of Union 1707, two simultaneous acts passed by the parliaments of England and Scotland. These created a political union between the Kingdom of England (consisting of England and Wales) and the Kingdom of Scotland. This event was the result of the Treaty of Union that was agreed on 22 July 1706. The Acts created a single Parliament of Great Britain at Westminster as well as a customs and monetary union. However, England and Scotland remained separate legal jurisdictions. In 1801, the Acts of Union 1800 united the Kingdom of Great Britain with the Kingdom of Ireland, through two similar independent acts of the Parliament of Great Britain and the Parliament of Ireland. This created the United Kingdom of Great Britain and Ireland on a similar basis to how England and Scotland had been united a century earlier. A campaign to repeal the Union in Ireland began immediately. A series of efforts in the late 19th and early 20th century to establish Home Rule for Ireland within the union were unsuccessful and, following the Anglo-Irish War and subsequent Anglo-Irish Treaty of 1922, most of Ireland left the union as the Irish Free State.