Realistic Horrors of the 1930-70s?

“Wake in Fright” would be a good example. It could all be true - nothing supernatural, no CGI… “The Housemaid” (1960) is another example, but I didn’t like it. “Rosemary’s Baby” would NOT be a good example (I won’t spoil why)… “Eyes Without a Face” and “The Face of Another” (even better) are very good, and have been classified under this category.

“Fist in Pocket” (Bellochio) might be one of my favorites, if not my favorite. Italy, 1965ish.

The original “M” might fall under this category, but I think many would consider it a thriller/mystery, but its great.

Les Diaboliques (1955), Peeping Tom (1960), if hallucination sequences are allowed then Repulsion (1965).

Wait Until Dark.

Psycho.

Anything by Alfred Hitchcock. Even The Birds with animals going crazy for no reason is not beyond possibility.

Jaws…The movie that apparently doesn’t have enough letters in it.

+1 for Repulsion

I was a veteran of all the horror genres through the 80’s when I first saw it and Carol’s crazy eyes when she stops, then continues slashing at the landlord still gives me the willies!

The Dark Eyes of London (UK title) aka The Human Monster (US title).

Mark of the Vampire and The She-Wolf of London had “Scooby-Doo” endings, where the supernatural element turns out to be a hoax.

You can fight me on whether it qualifies, but I’ll still praise The Abominable Dr. Phibes.

I can’t believe I forgot the great “Peeping Tom”… Are there ANY movies similar around that same time? The closest thing I can come up with is “The Collector”, which isn’t that close, but just as good.

What Ever Happened to Baby Jane? (1962) and Hush…Hush, Sweet Charlotte (1963)

Duel, Stephen Spielberg’s debut film.

Technically, there was nothing supernatural in the original Halloween, or Friday the 13th, or The Texas Chainsaw Massacre.

Do you consider I Spit on Your Grave or Last House on the Left to be horror?

Excellent choice. His best film, in my heretical opinion.

The Old Dark House where the terror is not supernatural at all.

Repulsion. Polanski also came close in The Tenant, up to the final twist.

Cat People?

I’ll throw in The Haunting (1963), based on Shirley Jackson’s The Haunting of Hill House. (And not to be confused with the 1999 ‘remake’) Haven’t read the book or seen this version in many years, but as I recall, there were no actual spookies shown, just implied, and a case could be made for it all being in Eleanor’s head. One of my favorites nonetheless (goes to hunt the DVD/Blu-ray…)

I saw “I Spit on Your Grave” and would consider it, yeah.

Hardly, considering the epilogue is spoken by the deceased character.

I’m not sure where other people draw the line between horror and thriller. For my money Robert Mitchum played the villain in a couple of the best non-supernatural horror films: Cape Fear (1962) and Night of the Hunter (1955). The latter is loosely based on the career of a real serial killer.

A couple that come to mind:
Fail Safe
The Andromeda Strain (some very early “CGI”, but on a screen, so I think it qualifies)