Sienna Miller was born in New York on the December 28, 1981, the youngest daughter of Ed and Jo Miller. She spent the majority of her childhood in London and Wiltshire. She was educated at Heathfield School in Berkshire where she showed a keen interest in the theatre, both recreationally and as part of her A Level curriculum.

After a year out traveling she went on to study drama at the Lee Strasberg Institute in New York. In 2000 she starred in the off-Broadway production of "Independence" at the Neighbourhood Playhouse. Miller's breakthrough came in 2001 with a role in the BBC series BEDTIME. She then went on to land the female lead role alongside Mark Valley, in KEEN EDDIE, created by J.H. Wyman, a sitcom about a New York City policeman who is sent to London and ends up sharing a flat with a beautiful young woman named Fiona, (Miller).

Sienna's film debut came in LAYER CAKE the Matthew Vaughn hit film based on JJ Connelly's London crime novel about a successful cocaine dealer XXXX (Daniel Craig) who earned a respected place among England's Mafia elite and plans an early retirement from the business. Sienna plays the alluring Tammy who captivates and distracts XXXX.

Sienna was then cast in the part of Nikki, a beautiful but unstable party girl, in Charles Shyer's high profile remake of the1960's classic ALFIE. She starred alongside Jude Law, Susan Sarandon, Marisa Tomei, Jane Krakowski and Nia Long. Charles Shyer says of Sienna, "I filmed a screen test with her and Jude and when he and I watched it, we were just blown away: not just by her breathtaking beauty on screen but also by her real, rare acting ability."

Sienna starred opposite Heath Ledger in Lasse Hallström's production of CASANOVA. She plays the part of Francesca, the only woman Casanova fails to seduce. Lasse Hallström says he cast Sienna after "a couple of really classy auditions." He comments on her role saying that "Francesca is an early feminist, and I wanted someone with a strong personality and intelligence, Sienna has the kind of charisma and charm that makes you believe in a character. I think she is a natural talent."

Sienna was cast in the part of Celia in the Young Vic's production of Shakespeare's "As You Like It," at the Wyndhams Theatre in London's West End. She starred alongside Helen McCrory, Dominic West and Reece Shearsmith.

Filmography

• Stardust (2007)
• Camille (2007)
• The Mysteries of Pittsburgh (2007
• Interview (2007)
• Factory Girl (2006)
• Casanova (2005)
• Alfie (2004)
• Layer Cake (2004)
• "Keen Eddie" (13 episodes, 2003-2004)
• "Bedtime" (2001) TV Series
• "The American Embassy" (1 episode, 2002)
• The Ride (2002)
• High Speed (2002)
• South Kensington (2001) (as Sienna Rose)