Producer Francis Ford Coppola had originally planned to direct the film himself as a companion piece to Dracula (1992), but eventually stepped back to let Kenneth Branagh direct. Coppola later regretted his decision after several disagreements with Branagh during filming.
The producers were hesitant about casting John Cleese as Professor Waldman since he was considered a comic actor with the looks to match. To make Cleese appear more serious, they fitted him with a prosthetic chin and teeth that made his looks more sharp and grave.
The amniotic fluid in which the Creature was brought to life, was really boiling gelatin. During filming, Robert De Niro and Kenneth Branagh slipped and fell in the stuff so much, that a huge split appeared in De Niro's prosthetic suit, which had to be avoided by the cameras.
Kenneth Branagh was keen to cast Gérard Depardieu as the Creature, but Columbia Pictures felt that he would not have strong enough box-office appeal. Branagh later cast Depardieu as Reynaldo in Hamlet (1996).
During his conversation with the Creature in the ice caves, Frankenstein remarks that "There was something at work in my soul which I do not understand". This line is taken almost word for word from the original novel, though there it appears in a letter from Captain Robert Walton to his sister, regarding his desire for exploring, and reads "there IS something at work...".
The trivia items below may give away important plot points.
This film contains several references to previous Frankenstein films: The Creature is brought to life in a metallic vat, as in Frankenstein (1910). Victor cuts an executed criminal from a hangman's noose, and uses the body for his experiments, as in Frankenstein (1931) and Young Frankenstein (1974). The Creature is reanimated with electrical charges. This is an invention of Hollywood. Mary Shelley does not specify in the novel how Victor creates or animates the Creature. Once the Creature comes to life, Victor triumphantly shouts, "It's alive!" The Creature's first spoken word is "friend". This is also the Creature's most frequently-used word, when he learns to speak in Bride of Frankenstein (1935). Victor uses the brain of a brilliant scientist and mentor for his Creature, as in The Curse of Frankenstein (1957). Justine Moritz's role is also expanded, and is made to fall in love with Victor in both films. Victor's mentor, who paved the road for his experiments, brings a severed arm back to life, and shows it to Victor, as in Frankenstein: The True Story (1973). The Creature hides in some cottagers' pigsty, and secretly learns to speak and read from observing them through a peephole. In the book, the cottagers are foreign refugees. In this film, the cottagers are simply local townsfolk. This variation on the novel was first used in Terror of Frankenstein (1977). Victor revives a mangled and hideous Elizabeth after the Creature murders her, and Victor and the Creature then engage in a battle for her affection. Horrified, the reanimated Elizabeth takes her own life. The same events take place, almost exactly, in Roger Corman's Frankenstein Unbound (1990). A cholera epidemic sweeps through Ingolstadt, leaving Victor to believe that the Creature died from disease. Frankenstein (1992) also featured a cholera epidemic under very similar circumstances, even though it is not present in the novel.