 | Keira Knightley als Georgiana Cavendish, Duchess of Devonshire |
 | Ralph Fiennes als Duke of Devonshire |
 | Charlotte Rampling als Lady Spencer |
 | Dominic Cooper als Charles Grey |
 | Hayley Atwell als Bess Foster |
 | Simon McBurney als Charles Fox |
 | Aidan McArdle als Richard Brinsley Sheridan |
 | John Shrapnel als General Grey |
 | Alistair Petrie als Heaton |
 | Patrick Godfrey als Dr. Neville |
 | Michael Medwin als Speechmaker |
 | Justin Edwards als Macaroni |
 | Richard McCabe als Sir James Hare |
 | Calvin A. Dean als Devonshire House Servant (as Calvin Dean) |
 | Hannah Stokely als Devonshire House Maid |
 | Andrew Armour als Burleigh |
| Emily Jewell als Nanny |
 | Bruce Mackinnon als Sir Peter Teazle |
 | Georgia King als Lady Teazle |
 | Luke Norris als Footman |
| Eva Hrela als Charlotte (Age 3) |
| Poppy Wigglesworth als Charlotte (Age 9) |
| Emily Cohen als Harryo |
| Mercy Fiennes Tiffin als Little G |
| Sebastian Applewhite als Augustus |
| Angus McEwan als Lord Robert |
 | Kate Burdette als Lady Harriet |
 | Laura Stevely als Lady Elizabeth |
 | Benjamin Noble als Lord Ambrose (as Ben Garlick) |
 | Max Bennett als Lord Walter |
 | Camilla Arfwedson als Lady Charlotte |
| Fiona Sheehan als Young Girl in Theatre |
| Sarah Wyatt als Servant Girl |
 | Thomas Arnold als Dealer |
 | Gilbert Wynne als Althorpe Servant |
| Richard Curzon als Heaton's Clerk |
| Sophia Johnston als Guest at Lady Melbourne's Ball |
| Katerina Tana als Guest at Lady Melbourne's Ball |
 | Clive Pearse als Narrator |
| David M. Thompson | Executive Producer |
| Gabrielle Tana | Producer |
| Gyula Pados | Director of Photography |
| Jeffrey Hatcher | Screenplay |
| Michael Kuhn | Producer |
| Masahiro Hirakubo | Editor |
| Carolyn Marks Blackwood | Executive Producer |
| Rachel Portman | Original Music Composer |
| Anders Thomas Jensen | Screenplay |
| Saul Dibb | Director |
| Rodrigo Gutierrez | Additional Camera |
| Saul Dibb | Screenplay |
| Adam Gascoyne | Visual Effects Supervisor |
| Vince Madden | Rigging Gaffer |
| Jill McCullough | Dialect Coach |
| Rachael Speke | Makeup Artist |
| Stephanie Hovette | Wigmaker |
| Francesca Jaynes | Choreographer |
| Jonathan Dixon | Digital Intermediate |
| Yann McCullough | Music Editor |
| Amanda Foreman | Novel |
| Andrea King | Foley |
| Simon Allmark | Visual Effects Editor |
| Josh Sutcliffe | Digital Intermediate |
| Neil Williams | First Assistant Editor |
| Corinne Bossu | Makeup Artist |
| John Colley | Gaffer |
| Catherine Hodgson | Supervising Sound Editor |
| Fran Needham | Hairstylist |
| Muffin Green | Property Master |
| Tapio Salmi | Makeup Artist |
| Michael Carlin | Production Design |
| Rebecca Alleway | Set Decoration |
| Roberto Cappannelli | Sound Re-Recording Mixer |
| Paul Hamblin | Sound Re-Recording Mixer |
| Gerry Vasbenter | Camera Operator |
| Marcus Alexander | Digital Intermediate |
| Fay McConkey | Visual Effects Producer |
| Charlie Noble | Visual Effects Supervisor |
| Peter Mountain | Still Photographer |
| Karen Wakefield | Art Direction |
| James Collins | Assistant Art Director |
| Emma Davie | Unit Publicist |
| Ben Gladstone | Location Manager |
| Michael O'Connor | Costume Design |
| Louise Fisher | Makeup Artist |
| Ed Cross | Visual Effects Editor |
| Becky Roberts | Visual Effects Producer |
| Élodie Ichter | Digital Intermediate |
| Sam Donovan | Script Supervisor |
| Andie Derrick | Foley |
| Christine Langan | Executive Producer |
| Mark Woolley | Associate Producer |
| Malcolm Ritchie | Associate Producer |
| Andrew Warren | Line Producer |
| Colleen Woodcock | Co-Producer |
| Alexandra Arlango | Co-Producer |
| François Ivernel | Executive Producer |
| Amanda Foreman | Executive Producer |
| Cameron McCracken | Executive Producer |
| Jill Tandy | Associate Producer |
| Andrew Semans | Associate Producer |
| Daniel Phillips | Makeup Designer |
| Jan Archibald | Hair Designer |
| Jeff Richardson | Dialogue Editor |
| Howard Halsall | Dialogue Editor |
