The Conservative Party, officially the Conservative and Unionist Party, is a centre-right political party in the United Kingdom. It is currently the governing party, having been so since the 2010 general election, where a coalition government with the Liberal Democrats was formed. In 2015, the Conservatives led by David Cameron won a surprise majority and formed the first majority Conservative government since 1992. However, the snap election on 8 June 2017 resulted in a hung parliament, and the party lost its parliamentary majority. It is reliant on the support of a Northern Irish political party, the Democratic Unionist Party (DUP), in order to command a majority in the House of Commons through a confidence-and-supply deal. The party leader, Theresa May, has served as both Leader of the Conservative Party and Prime Minister since July 2016. It is the largest party in local government with 9,008 councillors. The Conservative Party is one of the two major contemporary political parties in the United Kingdom, the other being its modern rival, the Labour Party.
The Conservative Party was founded in 1834 from the Tory Party—giving rise to the Conservatives' colloquial name of Tories—and was one of two dominant political parties in the nineteenth century, along with the Liberal Party. In the 1890s, it formed a coalition government with the Liberal Unionist Party, a break-away faction of the Liberal Party, and in 1912 the two merged to form the Conservative and Unionist Party. In the 1920s, the Liberal vote greatly diminished and the Labour Party became the Conservatives' main rivals. Conservative Prime Ministers led governments for 57 years of the twentieth century, including Winston Churchill (1940–1945, 1951–1955) and Margaret Thatcher (1979–1990). Thatcher's tenure led to wide-ranging economic liberalisation. The Conservative Party's domination of British politics throughout the twentieth century has led to them being referred to as one of the most successful political parties in the Western world.
The Conservatives are the second largest British party in the European Parliament, with eighteen MEPs, and sit with the European Conservatives and Reformists (ECR) parliamentary group. The party is a member of the Alliance of Conservatives and Reformists in Europe (ACRE) Europarty and the International Democrat Union (IDU).
The party is the second-largest in the Scottish Parliament and the second-largest in the Welsh Assembly. The Conservatives were formerly allied to the Ulster Unionist Party (UUP) in Northern Ireland but there is now a separate Northern Ireland Conservative party similar to the Welsh and Scottish Conservative parties. The party is also organised in the British Overseas Territory of Gibraltar.