Ellis was born in San Francisco, California, and raised on her grandmother's farm in Mississippi. She attended Tougaloo College before transferring to Brown University, where she completed her Bachelor of Arts in African-American studies, while also studying acting with Jim Barnhill and John Emigh. She went on to study acting in the Graduate Acting Program at New York University. She is a member of Delta Sigma Theta Sorority. Attended Tougaloo College in Tougaloo, Mississippi before she transferred to Brown University, where she completed her undergraduate studies.
In January 2004, she performed in Regina Taylor's play Drowning Crow, at the Manhattan Theatre Club.