Roger Corman decided to do an H.P. Lovecraft story as a break from his Edgar Allan Poe series while keeping the elements that made it successful. American-International took no chances. It gave the film a Poe title and marketed it as another in the series.
The title derives from a poem by Edgar Allan Poe which is contained within the text of his classic short story "The Fall Of The House Of Usher," where the ruined palace serves as a metaphor for the mind of the protagonist, Roderick Usher. Roger Corman had, of course, filmed "The Fall Of The House Of Usher" (with Vincent Price as Roderick) in 1960, the first film in his Poe series.
This film represents the first time that a literary work by H.P. Lovecraft was adapted for the screen. The author completed it in 1927, but it was not published until after his death.
The footage scene of the castle interior is similar to a scene in The Raven (1963) which was also directed by Roger Corman. Also the shots of the castle from the outside under thunder and lightning and waves breaking off rocks appear in both movies.
The last theatrical film appearance of Debra Paget.