Silent Night, Deadly Night
This 1980 slasher movie was intended to be just like the other popular slasher films that are connected to holidays. However, all the other slasher films are more connected to holidays that aren't Christmas. Parents in Brooklyn, Chicago, and Milwaukee all protested this film, which ended up getting the movie much more attention than its traditional marketing route got. So, in the end, the movie was boycotted, which is practically just an unofficial ban.
Haxan
This Swedish silent film was banned in the United States because it depicted acts of witchcraft and satanism. Haxan was a large proponent behind the "satanic panic" of the 1980s because of its re-cut and re-release that came out in 1960.