Keira Knightley & Ralph Fiennes in The Duchess (2008) The Duchess (2008) is an interesting period piece about the marriage of the 25 year-old William Cavendish, 5th Duke of Devonshire, to 17 year-old Georgiana Spencer in the late 18th century. Keira Knightley (23) portrays Georgiana opposite Ralph Fiennes (46) as the […]