Directed by D.W. Griffith, released in 1915

Why was DW Griffiths film Birth of a Nation so successful when it was released in 1915  and why is it so controversial now?​

It was so successful as it was a full length feature film (3 hours) that had very high production quality. It was accompanied by a main organ with tunes such as Ride of the Valkyries.

The black people were shown as being drunk and trying to sexual assault others. It contained the KKK who were shown as heroes. Although the KKK was fully gone, as the film was still being watched into the 1920s, more Klan chapters formed and membership reportedly reached into the millions. This released an outburst of racism

References: https://www.history.com/news/kkk-birth-of-a-nation-film