The United Kingdom is a state made up of the historic countries of England, Wales and Scotland, as well as Northern Ireland. It is known as the home of both modern parliamentary democracy and the Industrial Revolution.
Two world wars and the end of empire diminished its role in the 20th Century, and the 2016 referendum vote to leave the European Union has raised significant questions about the country's global role.
Nonetheless, the United Kingdom remains an economic and military power with great political and cultural influence around the world.
UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND: FACTS
- Capital: London
- Area: 242,945 sq km
- Population: 67.7 million
- Languages: English, also Scots, Ulster Scots, Scottish Gaelic, Irish, Welsh, Cornish
- Life expectancy: 79 years (men) 83 years (women)
Head of state: King Charles III
His Majesty King Charles III ascended to the throne in September 2022, on the death of his mother Queen Elizabeth II.
In September 2015, she had become Britain's longest-reigning monarch, surpassing the record of her great-great grandmother Queen Victoria.
King Charles is at 73 the oldest person to have ascended to the throne. He is also head of state of several independent countries in the Commonwealth.
As a constitutional monarch, his role in the legislative process is largely ceremonial.
Prime Minister: Rishi Sunak
The UK's first British Asian prime minister, Mr Sunak took over from the previous prime minister, Liz Truss, in October 2022, just 49 days after she herself had taken over from Boris Johnson. Mr Truss was forced to resign after big tax cuts in a her mini-budget prompted financial turmoil.
Mr Sunak became leader of the Conservative party without a ballot of its members when his only remaining rival Penny Mordaunt withdrew.
Ms Truss had became prime minister after defeating Mr Sunak earlier in a ballot of Tory members during the summer, winning over members with her tax-cutting economic agenda.
Mr Sunak faces the tasks of managing government spending, rising inflation and energy prices - especially in the wake of Russia's invasion of Ukraine.
The UK has a strong tradition of public service broadcasting and an international reputation for creative programme-making.
The BBC began daily radio broadcasts in 1922 and quickly came to play a pivotal role in national life. The corporation is funded by a licence fee, which every household with a TV set must pay.
Hundreds of privately-owned radio and TV stations now compete with the BBC for listeners and viewers.
There are many national and local newspapers, but print circulations have been sliding while online readership has surged.
There were 65 million internet users by July 2022, comprising 95% of the population (Worldinternetstats.com).
Some key dates in modern British history:
1801 - United Kingdom formed by union of the kingdoms of Great Britain and Ireland.
1815 - Role in defeating Napoleon's French Empire leads to Britain becoming pre-eminent imperial power.
1830s - Electoral reform acts begin steady move towards primacy of House of Commons and universal suffrage.
1840s - British industrial power harnessing technological change and boosts free trade and investment worldwide, reaching its peak in the second half of the 19th century.
1880s - Devolved government for Ireland becomes a major political issue, splitting Liberal Party and reviving a violent Irish separatist movement.
1914-18 - World War One.
1916 - Nationalists stage Easter Rising, seizing the General Post Office in Dublin and proclaiming an independent Irish republic. The rising is crushed by the British who execute its leaders.
1919 - Led by Éamon De Valera, the nationalist movement Sinn Féin ('We Ourselves') sets up a Dublin assembly, the Dáil Éireann, which again proclaims Irish independence. A guerrilla campaign by the Irish Republican Army, or IRA, against British forces begins with heavy casualties on both sides.
1921 - Anglo-Irish Treaty establishes the Irish Free State, partitioned from Northern Ireland which remains part of the United Kingdom of Great Britain and Northern Ireland.
1924 - First UK government led by the Labour party under Prime Minister Ramsay MacDonald.
1931 - Economic crisis. Millions are unemployed. National Government coalition formed.
1936 - King Edward VIII abdicates over relationship with an American divorcee, Wallis Simpson.
1939 - Germany invades Poland. UK declares war on Germany.
1940 - Winston Churchill becomes prime minister.
1944 - Allied troops invade France from Britain on D-Day (6th June) and begin to fight their way towards Germany.
1945 - Germany surrenders. Labour leader Clement Atlee is elected prime minister to replace Winston Churchill. The new Labour government introduces the welfare state.
1945 - The UK becomes a permanent member of the UN Security Council.
1948 - National Health Service is established.
1949 - The UK is one of the founder members of Nato.
1956 - UK intervenes in Suez Canal Zone, but withdraws under pressure from the US.
1961 - UK application to join European Economic Community vetoed by French President Charles de Gaulle.
1960s - Decolonisation of former British-controlled territories gathers pace.
1969 - British troops are sent to help quell communal unrest in Northern Ireland, which marks the start of The Troubles, triggered by the disputed status of Northern Ireland within the UK and a rising sense of injustice among large sections of the Catholic population. More than 3,000 people are killed between 1969-98.
1973 - The UK joins the European Economic Community, which is endorsed in a referendum two years later.
1979 - Conservative Margaret Thatcher begins move towards deregulation of economy.
1982 - Argentina invades the Falklands Islands in the South Atlantic. The UK dispatches a task force, which re-takes them.
1984 - The IRA attempts to assassinate Margaret Thatcher in her hotel in Brighton. Several killed and injured by a bomb blast, but the prime minister escapes unhurt.
1997 - Referendums in Scotland and Wales back the creation of separate assemblies, which are inaugurated in 1999.
1998 - Good Friday Agreement on a political settlement for Northern Ireland is approved by voters in the Republic of Ireland and Northern Ireland.
2012 - Britain hosts the 2012 Summer Olympics and Paralympics.
2014 - Voters in Scotland reject independence in a referendum, with 55% opting to remain part of the UK and 45% favouring independence.
2016 - UK votes to leave the European Union.
2020 - Britain formally leaves the European Union.