First reported by Knightley fansite KeiraWeb we learn that Keira will be playing the 18th century aristocrat Georgiana, duchess of Devonshire, in Saul Dibb's The Duchess, co-financed by Pathe and BBC Films.

The film was adapted from Amanda Foreman's best-selling biography telling the story of Georgina, an ancestor of Princess Di, who lived an extravagant, profligate and promiscuous life of political and romantic intrigue, becoming an important powerbroker amid Blighty's ruling elite but also running up catastrophic gambling debts. She was alternately feted and reviled, and widely caricatured by the popular press.

The film begins shooting in October.