The Labour Party is a centre-left political party in the United Kingdom, and one of the two main British political parties along with the Conservative Party. The Labour Party was founded in 1900 and overtook the Liberal Party in general elections during the early 1920s, forming minority governments under Ramsay MacDonald in 1924 and 1929–1931. The party was in a wartime coalition from 1940 to 1945, after which it formed a majority government under Clement Attlee. Labour was also in government from 1964 to 1970 under Harold Wilson and from 1974 to 1979, first under Wilson and then James Callaghan.

The Labour Party was last in national government between 1997 and 2010 under Tony Blair and Gordon Brown, beginning with a majority of 179, reduced to 167 in 2001 and 66 in 2005. Having won 258 seats in the 2010 general election, Labour is the Official Opposition. Labour has a minority government in the Welsh Assembly, is the main opposition party in the Scottish Parliament and has 13 MEPs in the European Parliament, sitting in the Socialists and Democrats (S&D) group. The Labour Party is a member of the Socialist International and Party of European Socialists. The Party's current leader is Ed Miliband MP.

Edward Samuel Miliband (born 24 December 1969) is a British Labour Party politician, currently the Leader of the Labour Party and Leader of the Opposition. He has been the Member of Parliament (MP) for the South Yorkshire constituency of Doncaster North since 2005 and served in the Cabinet from 2007 to 2010 under Prime Minister Gordon Brown. He and his brother, David Miliband, were the first siblings to sit in the Cabinet simultaneously since Edward, Lord Stanley, and Oliver Stanley in 1938.

Born in London, Miliband graduated from Corpus Christi College, Oxford and the London School of Economics, becoming first a television journalist and then a Labour Party researcher, before rising to become one of Chancellor Gordon Brown's confidants and Chairman of HM Treasury's Council of Economic Advisers.

As Prime Minister, Gordon Brown appointed Miliband as Minister for the Cabinet Office and Chancellor of the Duchy of Lancaster on 28 June 2007. He was subsequently promoted to the new post of Secretary of State for Energy and Climate Change, a position he held from 3 October 2008 to 11 May 2010. On 25 September 2010, he was elected Leader of the Labour Party.

Anthony Charles Lynton Blair (born 6 May 1953) is a British Labour Party politician who served as the Prime Minister of the United Kingdom from 2 May 1997 to 27 June 2007. He was the Member of Parliament (MP) for Sedgefield from 1983 to 2007 and Leader of the Labour Party from 1994 to 2007. He resigned from all of these positions in June 2007.

Blair was elected Leader of the Labour Party in the leadership election of July 1994, following the sudden death of his predecessor, John Smith. Under his leadership, the party used the phrases "New Labour" and "New Socialism" to define its policy, and moved away from its support of state socialism since the 1960s and created a new version of the ethical socialism that was last pursued by Clement Attlee. Critics of Blair claim that "New Labour" did not adhere to socialism as claimed, and that it effectively advocated capitalism. Blair subsequently led Labour to a landslide victory in the 1997 general election. At 43 years old, he became the youngest Prime Minister since Lord Liverpool in 1812. In the first years of the New Labour government, Blair's government implemented a number of 1997 manifesto pledges, introducing the minimum wage, Human Rights Act and Freedom of Information Act, and carrying out devolution, establishing the Scottish Parliament, the National Assembly for Wales, and the Northern Ireland Assembly.