The United Kingdom has historically played a leading role in developing parliamentary democracy and in advancing literature and science. At its zenith in the 19th century, the British Empire stretched over one-fourth of the earth’s surface. The first half of the 20th century saw two World Wars seriously deplete the UK’s strength and the Irish Republic withdraw from the union. The second half witnessed the dismantling of the Empire and the UK rebuilding itself into a modern and prosperous European nation. As one of five permanent members of the UN Security Council and a founding member of NATO and the Commonwealth of Nations, the UK pursues a global approach to foreign policy. The Scottish Parliament, the National Assembly for Wales, and the Northern Ireland Assembly were established in 1998.

The UK was an active member of the EU after its accession in 1973, although it chose to remain outside the Economic and Monetary Union. However, motivated in part by frustration at a remote bureaucracy in Brussels and massive migration into the country, UK citizens on 23 June 2016 voted by 52 to 48 percent to leave the EU. The UK became the first country to depart the EU on 31 January 2020, after prolonged negotiations on EU-UK economic and security relationships had been hammered out.