Tombs of the Blind Dead is a spanish horror film written and directed by Amando de Ossorio in 1971. In it, the Knights Templar(a monastic order) come back from the dead as Zombies.
Well, maybe not.
While this film is commonly described as a Zombie movie, Ossorio believes that his monsters more closely resemble mummies. Not only that, but the Templars from Tombs of the Blind Dead are not quite mindless.
It is worth watching non-the-less as it does have many of the underlying motifs of good zombie films and as a twist, the monsters are blind (the eyes of their corpses were pecked out) and ride horses pretty much through the entire film, which should be all you need to know.