Birth of a Nation (1915)
For better and worse, Birth of a Nation is Griffith's finest work and a landmark of American cinema.
It was huge: 12,500 feet, 187 minutes long, over 13,000 individual shots.
One of the most widely seen and profitable films of the 20th century. It made about $20 million (about $471 million in 2016 dollars). It would be 1937 before a film would do better (that was Snow White and the Seven Dwarfs).
One reason the film did so well was the opening admission price of $2...the highest yet charged. For that fee, viewers saw the film with accompaniment by a 47 piece orchestra. The $2 charge had great publicity value at a time when workers were making $1-$2 per day. After the opening run, the price dropped and enormous numbers saw the film.
