1. The African-Americans were played by white actors in blackface as unintelligent and sexually aggressive people towards white women. They were depicted as lascivious villains who take over the South and treat it as their hedonistic playground. With the help of the carpetbaggers, black people assume control over government, using their power to instill laws that allow black-white intermarriage and force whites to salute black soldiers. Also in keeping with the prevailing perception of blacks by whites at the time is the inclusion of the pure white girl being threatened by black men. I don't feel as though any part of the depiction was accurate as it seemed a little bit racial.
2. Yes, I think the historical period in America greatly influenced the director's decision to portray the blacks in that way.
3. The National Association for the Advancement of Colored People, protested premieres of the film in numerous cities. It also conducted a public education campaign, publishing articles protesting the film's fabrications and inaccuracies, organizing petitions against it, and conducting education on the facts of the war and Reconstruction.
When the film was shown, riots broke out in Boston, Philadelphia and other major cities. Other cities refused to allow the film to open. The film's inflammatory character was a catalyst for gangs of whites to attack blacks. In Indiana, after seeing the film, a white man murdered a black teenager. I think people responded in this way