Duke of Devonshire a separate title from that of Earl of Devon, which still belongs to the Courtenay family. The fifth Duke and Duchess of Devonshire are portrayed in the 2008 film "The Duchess" directed by Saul Dibb. The film is based on Amanda Foreman's biography of the scandalous 18th-century English aristocrat Georgiana Cavendish, Duchess of Devonshire (portrayed by Keira Knightley) and her relationship with the Duke (Ralph Fiennes) and his next wife, Lady Elizabeth Foster. Along with Jane Austen, the fifth Duke and his second wife appear, soon after Georgiana's death, in "Jane and the Stillroom Maid", a murder mystery by Stephanie
Deborah Cavendish, Duchess of Devonshire Deborah Cavendish, Duchess of Devonshire Deborah Vivien Cavendish, Duchess of Devonshire, (born Deborah Freeman-Mitford and latterly Deborah, Dowager Duchess of Devonshire; 31 March 1920 – 24 September 2014) was an English aristocrat, writer, memoirist and socialite. She was the youngest and last surviving of the six Mitford sisters, who were prominent members of English society in the 1930s and 1940s. Known to her family as "Debo", Deborah Mitford was born in Asthall Manor, Oxfordshire, England. Her parents were David Freeman-Mitford, 2nd Baron Redesdale (1878–1958), son of Algernon Freeman-Mitford, 1st Baron Redesdale, and his wife, Sydney (1880–1963), daughter of Thomas Gibson