Sienna Rose Diana Miller was born in New York City, but spent most of her childhood in London, United Kingdom. Her father, Edwin "Ed" Miller, is an American-born investment banker and dealer in Modern Chinese paintings, while her mother, Josephine "Jo" Miller, is a South African model and yoga instructor who previously worked as a personal assistant to David Bowie.
Raised alongside her older sister, Savannah Miller, Sienna's family moved to Chelsea, London, when she was just 18 months old. Her weekends were often spent horse riding at her godmother's farmhouse in Wiltshire. When Sienna was six years old, her parents got divorced, and she and her sister moved to Parsons Green with their mother, who was undergoing treatment for breast cancer.
After her parents' divorce, Sienna's father remarried three times and relocated to the Virgin Islands. At the age of eight, Sienna moved away to Heathfield boarding school in Ascot, where she developed a passion for lacrosse and acting.
Upon turning 18, Sienna returned to New York City and enrolled at the Lee Strasberg Theatre and Film Institute. She then traveled, modeled, and took on small film roles, eventually landing a part in the BBC sitcom Bedtime (2001). Her breakthrough film role was as Daniel Craig's love interest in Matthew Vaughn's Layer Cake (2004).
Sienna's film credits include Alfie (2004),Casanova (2005),Factory Girl (2006),and Interview (2007),opposite Steve Buscemi. She received a British Independent Film Award nomination for Best Supporting Actress for her role in The Edge of Love (2008),alongside Keira Knightley, with whom she formed a close friendship.
In addition to her film work, Sienna has also carved out a notable theatre career, with credits including the role of Celia in the Young Vic production of "As You Like It" and the Broadway production of Patrick Marber's "After Miss Julie", opposite Jonny Lee Miller. Her most recent stage performance was in Terence Rattigan's critically-acclaimed "Flare Path", directed by Sir Trevor Nunn, held at London's Theatre Royal Haymarket.
