The Technical and Cultural Importance of Birth of a Nation
Birth of a Nation, because it was the first true feature film, had an enormous technical and cultural impact.
Technically, it showed the basic techniques that were to be used in film over the next several decades.
Financially, it showed that feature films could be far more successful than shorts.
Culturally it deeply influenced the way (mostly white) Americans understood the Civil War, led to a revival of the KKK, created KKK ritual and regalia, and continues to influence American understandings (and politics) today.
The importance of Birth of a Nation was undoubtedly increased by the fact that President Woodrow Wilson screened it in the White House. Wilson was widely reported, both at the time and in subsequent histories, as saying that the film was "like writing history with lightening." and often reported as saying that his only regret "was that is is all so terribly true." It's not clear that he ever said any of this but, many versions of the film carried the alleged Wilson "lightening" quote. Although Wilson was not a supporter of the KKK, he clearly agreed with the film's main thesis: that white people needed to use violence to save the South from Black people. Wilson, not coincidently, was from Virginia. It would be hard to overstate the importance of the film being given presidential support, especially in the hyper-patriotic atmosphere of the years around World War I. On the other hand, the pioneering sociologist Thorstein Veblen (1857-1929) had a far more accurate and pithy reaction to the film. He said: "Never before have I seen such concise misinformation."