The Labour Party, commonly Labour, is one of the two main political parties in the United Kingdom, along with the Conservative Party. It sits on the centre-left of the left–right political spectrum, and has been described as an alliance of social democrats, democratic socialists and trade unionists. It has been the governing party since the 2024 general election. Keir Starmer has been Leader of the Labour Party since 2020 and Prime Minister of the United Kingdom since 2024. There have been twelve Labour governments and seven Labour prime ministers. The party meets annually during Autumn for the Labour Party Conference, during which delegates from local parties and trade unions vote on party policy, and senior figures address the audience from the Conference platform.
The Labour Party was founded in 1900, having emerged from the trade union movement and socialist parties of the 19th century. It was electorally weak before the First World War, but in the early 1920s overtook the Liberal Party to become the main opposition to the Conservative Party, and briefly formed a minority government under Ramsay MacDonald in 1924. In 1929 Labour for the first time became the largest party in the House of Commons, with 287 seats, but fell short of a majority, forming another minority government. In 1931, in response to the Great Depression, MacDonald formed a new government with Conservative and Liberal support, which led to his expulsion from the party. Labour was soundly defeated by his coalition in 1931, winning only 52 seats, but began to recover in 1935 with 154 seats.