The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain, is a sovereign island country

The UK spans the island of Great Britain, the northeast part of the island of Ireland, and many small islands. Northern Ireland is the only part of the UK with a land border, sharing it with the Republic of Ireland. Apart from this land border, the UK is surrounded by the Atlantic Ocean, the North Sea, the English Channel and the Irish Sea. The largest island, Great Britain, is linked to France by the Channel Tunnel.

The United Kingdom consists of England, Northern Ireland, Scotland and Wales. A unitary state with devolved national legislatures, the UK is governed by a parliamentary system with its seat of government in London, the capital. The UK is a constitutional monarchy with Queen Elizabeth II as the head of state. The Crown Dependencies of the Channel Islands and the Isle of Man, formally possessions of the Crown, are not part of the UK but form a federacy with it. The UK has fourteen overseas territories, all remnants of the British Empire, which at its height encompassed almost a quarter of the world's land surface, the largest empire in history. As a result of the empire, British influence can be observed in the language, culture and legal systems of many of its former colonies. Queen Elizabeth II remains the head of the Commonwealth of Nations and head of state of each of the Commonwealth realms.

The UK is a developed country, with the sixth (nominal GDP) or seventh (PPP) largest economy in the world. It was the world's first industrialised country and the world's foremost power during the 19th and early 20th centuries, but the economic cost of two world wars and the decline of its empire in the latter half of the 20th century diminished its leading role in global affairs. The UK nevertheless remains a major power with strong economic, cultural, military and political influence and is a nuclear power, with the second or third highest (depending on method of calculation) defence spending in the world. It is a member state of the European Union, holds a permanent seat on the United Nations Security Council, and is a member of the G8, NATO, OECD, WTO and the Commonwealth of Nations.

History

Main: History of the formation of the United Kingdom

On 1 May 1707, the United Kingdom of Great Britain, was created by the political union of the Kingdom of England (which included the once independent Principality of Wales) and the Kingdom of Scotland. This event was the result of the Treaty of Union that was agreed on 22 July 1706, and then ratified by both the Parliament of England and Parliament of Scotland each passing an Act of Union in 1707. Almost a century later, the Kingdom of Ireland, which had been brought under English control between 1541 and 1691, joined the Kingdom of Great Britain with the passing of the Act of Union 1800. Although England and Scotland had been separate states prior to 1707, they had been in personal union since the Union of the Crowns in 1603, when James VI King of Scots had inherited the throne of the Kingdom of England and Kingdom of Ireland. King James I, as he was styled outwith Scotland, then moved his court from Edinburgh to London.