Coppola has been criticized for not including an African American character in her film.
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She felt that treating slavery as a side-plot would be insulting.
Her decision to not include Mattie comes from respect because there are too many examples of slaves given a voice by white artists.
She did not think while doing her film, that it was not responsible to not deal with slavery and slaves characters in a movie set in Civil War. She has been thinking about this and will continue to do so.
Her artistic choices were criticized as insensitive when it was not her intention.
She hopes this discussion will bring attention to Hollywood that more films from the voices of filmmakers of color are needed and to include more points of views and histories.