This genre is a subgenre from  Horror Movies started with the movie: “Haxan: Witchcraft Through The Ages”, starting Benjamin Christensen,

who also wrote and directed the movie sing a historical study on Witchcraft. He started the project as a documentary and then he realize that to show his audience his research was to create a movie using everything he could to make them feel the and experience "witchcraft through the ages"

 using special effects including music. He was an expert on using classical music in movies.

Another important person in this genre is Mario Bava, with

movies like: Black Sunday (1960),  La Maschera del Demonio (1960),  The city of the Dead (1960), Black Sabbath (1963). His special effect expertise took him to the fame.

Links

http://shop/monstrous.com/witchcraft_movies_list.htm

http://members.tripod.com/mariobava/

http://www.mundofree.com/cine_nordico/Benjamin_Christensen.html