1915: D.W. Griffith's film "The Birth of a Nation" premieres in Los Angeles. The silent movie, based on the novel and play "The Clansman," was a commercial success, but was highly controversial due to its portrayal of black men (played by white actors in blackface) as unintelligent and sexually aggressive toward white women, and the portrayal of the Ku Klux Klan as a heroic force. When the film was shown, riots broke out in Boston, Philadelphia and other major cities. In response, several other cities refused to allow the film to open. The film has also been credited as groundbreaking for its innovative application of the medium of film, including pioneering such camera techniques as the use of panoramic long shots, the iris effects, still-shots, night photography and panning camera shots.