one of the main British political parties, on the political left, that has traditionally represented the interests of working people the Labour Party leader Culture The Labour Party has traditionally been supported by the trade unions. It developed from the Independent Labour Party and formed its first government in 1924 under Ramsay MacDonald. Other Labour prime ministers since then have been Clement Attlee (1945-51), Harold Wilson(1964-70), James Callaghan (1974-9), Tony Blair (1997-2007) and Gordon Brown (2007-10). In the 1980s and 1990s the party moved away from traditional left wing policies regarding public ownership of industry and giving up nuclear weapons. Because of these changes the party is now also known as New Labour. It was elected to government in 1997 under Tony Blair, with a large majority in the House of Commons. Opposition to New Labour policies and to the war in Iraq among traditional Labour Party members has led to a decline in party membership.