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 won the most seats in the House of Commons at the 2017 general election. However, it is reliant on the support of the Northern Irish party, the Democratic Unionist Party, in order to command the majority of the House of Commons. The party's leader, Theresa May, is currently serving as Prime Minister. It is the largest party in local government with 9,237 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's platform involves support for free market capitalism, free enterprise, fiscal conservatism, a strong national defence, deregulation, and restrictions on trade unions.
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. During the 1890s, it formed a coalition government with the Liberal Unionist Party, a break-away faction of the Liberal Party. In 1912, the two parties merged to form the current 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 (1940–45, 1951–55) and Margaret Thatcher (1979–90). 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.