Prior to watching The Birth of a Nation, I for some reason thought it was about the Roman Empire. Well let me tell you, if you're looking for a racist movie that’s definitely not about the Roman Empire but definitely is about the KKK "saving the day" against a bunch of assholes in blackface, do I have the movie for you.
In regards to its directing, The Birth of a Nation shows us that early filmmakers viewed their work as the most literal interpretation of “moving pictures”, as D.W. Griffith used the camera to show, never to tell, a story. The text cards we associate with silent films were rarely used to convey dialogue, but instead shown to title the following shot, as if the film were merely a series of paintings that when showed in in succession told a story.
Below is an example of this in which Griffith titles a shot and then shows us exactly the picture he just described.
It wasn't until Citizen Kane in 1941 that filmmakers used the camera to tell, not just show, a story.