In which year did this British peer and politician whose daughter was Henrietta Ponsonby, Countess of Bessborough pass away?
John Spencer, 1st Earl Spencer John Spencer, 1st Earl Spencer (19 December 1734 – 31 October 1783) was a British peer and politician.
William Cavendish, 6th Duke of Devonshire William George Spencer Cavendish, 6th Duke of Devonshire {'1': ", '2': ", '3': ", '4': "} (21 May 1790 – 18 January 1858), styled Marquess of Hartington until 1811, was a British peer, courtier, nobleman, and Whig politician. Known as the "Bachelor Duke", he was Lord Chamberlain of the Household between 1827 and 1828 and again between 1830 and 1834. The Cavendish banana is named after him.