Eliza was the daughter of an Indian attorney, who with her two older brothers lived on a Chippewa reservation. Eliza graduated from the school of arts highschool in Rochester, New York. She also graduated from the theater program at Northwestern University's National High School Institute , afterward she graduated from UCLA as a world arts and cultures major. Eliza has an accomplished voice and can speak French and Russian. Musically she is best known as "Blue girl", her alter ego. She succeeded voice actress Mary Kay Bergman as the lead female voice actor on the animated cartoon series South Park, a position she held until 2003.