Bill: You see this knife? I'm gonna teach you to speak English with this fucking knife!
In one scene where Bill is in the Mayor's office, the mayor is sitting behind his desk and holding a bunch of papers, and on the upper right hand corner of the papers is a paper clip. Paperclips were not invented until 1899.
At the end of the film you see two gravestones, "Priest" Vallon and William Cutting. Behind them is a river, with a view of lower Manhattan after that. You see a bridge being built, and the city growing and changing. The two men had to have been buried in Brooklyn, rather than Manhattan for this view.