Oh, I came in here to mention that the British Hammer films made a ton of horror movies during this period with about a 3rd or so featuring “satanic” themes. Including the OP’s “To the Devil a Daughter”. The other 2/3rd were more classic gothic themes that were already popular in British literature for more than 100 years; vampires, mummies, serial killers and ghosts.
And as for the UK being “post-Christian”, there’s still plenty of superstition to go around. I know more than a few British people who believe in ghosts.
Weren’t the last couple of Hammer’s Dracula films also in that “satanic” category? I know at least one even had “Satanic Rites of Dracula” as the title or alternate title. (On checking your link, it’s #42 on that list)
I think I rented that on VHS once in the late 90’s. Very odd movie if I remember it right about a satanic cult in 1970’s London bringing back Dracula or some such. Not at all what I’d expected when I asked my mom to bring back a Dracula movie when she went to the video store.
Night of the Demon is a different animal. The demon in there is very European; very old world; very druidic; you get the sense of it’s being connected throughout history to the ancient shadows of forgotten ancestors. It seemed to be more a fear of the “old ways,” like traditional British thrillers and ghost stories.
No one suggests that demonic storylines were invented out of whole cloth in the 70s; this thread is just an attempt to discuss the surge of such subject matter at that time.