The Duchess (2008)

Long before the concept existed, the Duchess of Devonshire, Georgiana Spencer, was the original "It Girl". Like her direct descendent Princess Diana, she was ravishing, glamorous and adored by an entire country. Determined to be a player in the wider affairs of the world, she proved that she could out-gamble, out-drink and outwit most of the aristocratic men who surrounded her. And when she tried to find her own way to be true to her heart and loyal to her duty, the resulting controversies and convoluted liaisons would leave all of London talking.

Official website: http://www.theduchessmovie.com/