Val Lewton did not like the article "I Walked With A Zombie" by Inez Wallace that had been optioned so he adapted the story to fit the novel "Jane Eyre" because he felt the article's plot was too clichéd.
The legal disclaimer at the end of the credits, which roll at the start of the film, makes light of the film's subject. The disclaimer states: "The characters and events depicted in this photoplay are fictional. Any similarity to actual persons, living, dead, or possessed, is purely coincidental."
In the script, the fictitious island is very explicitly identified as being owned by the United States. None of these items (such as a prominent American flag flying at the harbor) made it into the film, and items like the island's association with Ontario (where Betsy is from) suggest that it might instead be a current or former British colony.
Sir Lancelot wrote the song "Shame and Scandal in the Family" for this movie. In the early 1960s Lord Melody used the melody and the chorus and an old humorous story to create a new song, initially called "Wau Wau", though it became more familiarly known under its original title. The song was recorded by a variety of international artists (e.g.. The Kingston Trio, Odetta, Peter Tosh and The Wailers), even becoming a #1 hit in Australia. In the course of its life, the original writers have been ignored at times, with the authorship being attributed to a duo of Donaldson and Brown, instead of Sir Lancelot and Ardel Wray (the film's co-writer).
Hanging on the wall in Jessica's room is a copy of Arnold Bocklin's mysterious painting "Isle of the Dead," which would serve as the basis for another Lewton production with that title two years later.