Andrew Robert Buxton Cavendish, 11th Duke of Devonshire KG, MC, PC (2 January 1920 – 3 May 2004), styled Lord Andrew Cavendish until 1944 and Marquess of Hartington from 1944 to 1950, was a British Conservative and later Social Democratic Party politician. He was a minister in the government of Prime Minister Harold Macmillan (who was married to his aunt), but is best known for opening Chatsworth House to the public.