Gillian Leigh Anderson (born August 9, 1968) is an American actress, best known for her roles as FBI Special Agent Dana Scully in the American TV series The X-Files, Moro in the English dub of Princess Mononoke and Lady Dedlock in the BBC TV series Bleak House.

Anderson was born in Chicago, Illinois, the daughter of Rosemary Anderson, a computer analyst, and Edward Anderson, who owned a film post-production company. Soon after her birth, her family moved to Puerto Rico for 15 months and then to Crouch End and finally Harringay in London, so that her father could attend the London Film School. When Anderson was 11 years old, her family moved again, this time to Grand Rapids, Michigan. She attended Fountain Elementary and then City High-Middle School, a program for gifted students with a strong emphasis on the humanities; she graduated in 1986.

With her English accent and background, Anderson was mocked and felt out of place in the American Midwest and soon adopted a Midwest accent. In addition, she had her nose pierced in the early 1980s and dyed her hair various colors. Her high school classmates voted her as "Most Bizarre," "Class Clown", "Most Likely to go Bald" and "Most Likely to be Arrested." She was caught trying to jam the high school doors by filling their locks with glue on the eve of her graduation.