Keira Christina Knightley (; born 26 March 1985) is an English actress. Known for her work in both independent films and blockbusters, particularly period dramas, she has received several accolades, including nominations for two Academy Awards, three British Academy Film Awards, and a Laurence Olivier Award. In 2018, she was appointed an OBE at Buckingham Palace for services to drama and charity.

Born in London to actors Will Knightley and Sharman Macdonald, Knightley obtained an agent at age six and initially worked in commercials and television films. She had a minor role as Sabé in the space opera Star Wars: Episode I – The Phantom Menace (1999). Her breakthrough came when she played a tomboy footballer in the sports film Bend It Like Beckham (2002), and went on to achieve global stardom for playing Elizabeth Swann in the swashbuckler fantasy series Pirates of the Caribbean, beginning in 2003. She appeared in the romantic comedy Love Actually (2003) and was labelled a promising teen star.

For her portrayal of Elizabeth Bennet in the period romance Pride & Prejudice (2005), Knightley was nominated for the Academy Award for Best Actress. She starred in a number of more period pieces, playing a complex love interest in Atonement (2007), tastemaker Georgiana Cavendish in The Duchess (2008), and the titular socialite in Anna Karenina (2012). She forayed into contemporary dramas, appearing as an aspiring musician in Begin Again (2013) and a medical student in Jack Ryan: Shadow Recruit (2014). Knightley returned to historical films playing Joan Clarke in The Imitation Game (2014), earning her a nomination for the Academy Award for Best Supporting Actress, and starred as the eponymous writer in Colette (2018).

On stage, Knightley has appeared in two West End productions: The Misanthrope in 2009, which earned her an Olivier Award nomination, and The Children's Hour in 2011. She also starred as the eponymous heroine in the 2015 Broadway production of Thérèse Raquin. Knightley is known for her outspoken stance on social issues and has worked extensively with Amnesty International, Oxfam, and Comic Relief. She is married to musician James Righton and they have two daughters.