Nancy Jean Cartwright (born October 25, 1957) is an American voice actress, film and television actress, and comedian. She is known for her long-running role as Bart Simpson on the animated television series The Simpsons. Cartwright also voices other characters for the show, including Nelson Muntz, Ralph Wiggum, Todd Flanders, Kearney, and Database.

After continuing to search for acting work, in 1987 Cartwright auditioned for a role in a series of animated shorts about a dysfunctional family that was to appear on The Tracey Ullman Show. Cartwright intended to audition for the role of Lisa Simpson, the middle child; when she arrived at the audition, she found the role of Bart—Lisa's brother—to be more interesting. Matt Groening, the series' creator, allowed her to audition for Bart and offered her the role on the spot. She voiced Bart for three seasons on The Tracey Ullman Show, and in 1989, the shorts were spun off into a half-hour show called The Simpsons. For her subsequent work as Bart, Cartwright received a Primetime Emmy Award for Outstanding Voice-Over Performance in 1992 and an Annie Award for Best Voice.

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