when did she start her career?
She moved to Hollywood in 1978 and trained alongside voice actor Daws Butler.
Introduction
Cartwright was born in Dayton, Ohio. Cartwright moved to Hollywood in 1978 and trained alongside voice actor Daws Butler. 
who does the voice over for bart simpson Nancy Jean Cartwright
Her first professional role was voicing Gloria in the animated series "Richie Rich". Her first professional role was voicing Gloria in the animated series "Richie Rich" In 1976
Nancy Cartwright Nancy Cartwright Nancy Cartwright
Introduction Introduction Early life
Her first professional role was voicing Gloria in the animated series "Richie Rich", which she followed with a starring role in the television movie "Marian Rose White" (1982) and her first feature film, "" (1983). . Her first professional role was voicing Gloria in the animated series "Richie Rich", which she followed with a starring role in the television movie "Marian Rose White" (1982) and her first feature film, "" (1983).
 In 1976, Cartwright landed a part-time job doing voice-overs for commercials on WING radio in Dayton.
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Nancy Cartwright [SEP] Introduction
Nancy Jean Cartwright (born October 25, 1957) is an American actress and voice actress. 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, Database, and Maggie (previously voiced by fellow co-star, Yeardley Smith). Cartwright was born in Dayton, Ohio. Cartwright moved to Hollywood in 1978 and trained alongside voice actor Daws Butler. Her first professional role was voicing Gloria in the animated series "Richie Rich", which she followed with a starring role in the television movie "Marian Rose White" (1982) and her first feature film, "" (1983).