A vote of no confidence in the British Labour government of James Callaghan occurred on 28 March 1979. The vote was brought by opposition leader Margaret Thatcher and was lost by the Labour government by one vote (311 votes to 310), which was announced at 10:19 pm. The result mandated a general election which was won by Thatcher's Conservative Party. The last time an election had been forced by the House of Commons was in 1924, when Ramsay MacDonald, the first Labour Prime Minister, lost a vote of confidence. Labour politician Roy Hattersley later remarked that the vote marked "the last rites" of 'old Labour'. Labour did not return to government for another 18 years. The BBC has referred to the vote as "one of the most dramatic nights in Westminster history".

The House of Commons is the lower house of the Parliament of the United Kingdom. Like the upper house, the House of Lords, it meets in the Palace of Westminster located in London, England.

The House of Commons is an elected body consisting of 650 members known as members of Parliament (MPs). MPs are elected to represent constituencies by the first-past-the-post system and hold their seats until Parliament is dissolved.

The House of Commons of England started to evolve in the 13th and 14th centuries. In 1707 it became the House of Commons of Great Britain after the political union with Scotland. It assumed the title of "House of Commons of Great Britain and Ireland" after the political union with Ireland at the start of the 19th century. From 1800, the "United Kingdom" referred to was the United Kingdom of Great Britain and Ireland, and in 1922 became the United Kingdom of Great Britain and Northern Ireland after the independence of the Irish Free State. Accordingly, the House of Commons assumed its current title.

Under the Parliament Acts 1911 and 1949, the Lords' power to reject legislation was reduced to a delaying power. The government is solely responsible to the House of Commons and the prime minister stays in office only as long as they retain the confidence of a majority of the Commons.