The Unionist Party was the main centre-right political party in Scotland between 1912 and 1965. Independent from, although associated with, the Conservative Party in England and Wales, it stood for election at different periods of its history in alliance with a small number of Liberal Unionist and National Liberal candidates. Those who became members of parliament (MPs) would take the Conservative Whip at Westminster as the Ulster Unionists did until 1972. At Westminster, the differences between the Scottish Unionist and the English party could appear blurred or non-existent to the external casual observer, especially as many Scottish MPs were prominent in the parliamentary Conservative Party, such as party leaders Bonar Law (1911–1921 and 1922–1923) and Sir Alec Douglas-Home (1963–1965),