History of the United Kingdom

The history of the United Kingdom began in the early eighteenth century with the Treaty of Union and Acts of Union. The core of the United Kingdom as a unified state came into being in 1707 with the political union of the kingdoms of England and Scotland,^[1] into a new unitary state called Great Britain.^{[lower-alpha 1]} Of this new state of Great Britain, the historian Simon Schama said:

What began as a hostile merger would end in a full partnership in the most powerful going concern in the world... it was one of the most astonishing transformations in European history.^[2]

This article may be too long to read and navigate comfortably. When this tag was added, its readable prose size was 20,500 words. (August 2023)

The Act of Union 1800 added the Kingdom of Ireland to create the United Kingdom of Great Britain and Ireland.

The first decades were marked by Jacobite risings which ended with defeat for the Stuart cause at the Battle of Culloden in 1746. In 1763, victory in the Seven Years' War led to the growth of the First British Empire. With defeat by the United States, France and Spain in the War of American Independence, Great Britain lost its 13 American colonies and rebuilt a Second British Empire based in Asia and Africa. As a result, British culture, and its technological, political, constitutional, and linguistic influence, became worldwide. Politically the central event was the French Revolution and its Napoleonic aftermath from 1793 to 1815, which British elites saw as a profound threat, and worked energetically to form multiple coalitions that finally defeated Napoleon in 1815. The Tories, who came to power in 1783, remained in power (with a short interruption) until 1830. Forces of reform, often emanating from the Evangelical religious elements, opened decades of political reform that broadened the ballot, and opened the economy to free trade. The outstanding political leaders of the 19th century included Palmerston, Disraeli, Gladstone, and Salisbury. Culturally, the Victorian era was a time of prosperity and dominant middle-class virtues when Britain dominated the world economy and maintained a generally peaceful century from 1815 to 1914. The First World War (1914–1918), with Britain in alliance with France, Russia and the United States, was a furious but ultimately successful total war with Germany. The resulting League of Nations was a favourite project in Interwar Britain. However, while the Empire remained strong, as did the London financial markets, the British industrial base began to slip behind Germany and, especially, the United States. Sentiments for peace were so strong that the nation supported appeasement of Hitler's Germany in the late 1930s, until the Nazi invasion of Poland in 1939 started the Second World War. In the Second World War, the Soviet Union and the US joined the UK as the main Allied powers.

Britain was no longer a military or economic superpower, as seen in the Suez Crisis of 1956. Britain no longer had the wealth to maintain an empire, so it granted independence to almost all its possessions.^{[citation needed]} The new states typically joined the Commonwealth of Nations. The postwar years saw great hardships, alleviated somewhat by large-scale financial aid from the United States, and some from Canada. Prosperity returned in the 1950s. Meanwhile, from 1945 to 1950, the Labour Party built a welfare state, nationalized many industries, and created the National Health Service. The UK took a strong stand against Communist expansion after 1945, playing a major role in the Cold War and the formation of NATO as an anti-Soviet military alliance with West Germany, France, the United States, Italy, Canada and smaller countries. NATO remains a powerful military coalition. The UK has been a leading member of the United Nations since its founding, as well as numerous other international organizations. In the 1990s, neoliberalism led to the privatisation of nationalised industries and significant deregulation of business affairs. London's status as a world financial hub grew continuously. Since the 1990s, large-scale devolution movements in Northern Ireland, Scotland and Wales have decentralised political decision-making. Britain has moved back and forth on its economic relationships with Western Europe. It joined the European Economic Community in 1973, thereby weakening economic ties with its Commonwealth. However, the Brexit referendum in 2016 committed the UK to leave the European Union, which it did in 2020.

In 1922, 26 counties of Ireland seceded to become the Irish Free State; a day later, Northern Ireland seceded from the Free State and returned to the United Kingdom. In 1927, the United Kingdom changed its formal title to the United Kingdom of Great Britain and Northern Ireland,^[3] usually shortened to Britain and (after 1945) to the United Kingdom or UK.