Tim Burton has said the original poem was inspired after seeing Halloween merchandise display in a store being taken down and replaced by a Christmas display. The juxtaposition of ghouls and goblins with Santa and his reindeer sparked his imagination.
In 2001, Walt Disney Pictures began to consider producing a sequel, but rather than using stop motion, Disney wanted to use computer animation. Tim Burton convinced Disney to drop the idea. "I was always very protective of [Nightmare] not to do sequels or things of that kind," Burton explained. "You know, 'Jack visits Thanksgiving world' or other kinds of things just because I felt the movie had a purity to it and the people that like it."
(at around 13 mins) It is stated in "The Making of..." book that the most difficult shot to film in the entire movie is the shot in which Jack is reaching for the doorknob to Christmas Land. Viewers can see the perfect surround reflection of the forest around Jack in the background.
Danny Elfman found writing Nightmare's 10 songs as "one of the easiest jobs I've ever had. I had a lot in common with Jack Skellington." Having created demos of all the songs for the director's approval, Elfman had gotten really attached to Jack, since he could relate to being loved and famous (as he was lead singer of his band Oingo Boingo), but like Jack, he was no longer happy with his situation. Elfman mustered up all his courage to ask his friend and producer Tim Burton if he could voice Jack, but before he could finish, Burton simply told him "Danny, don't worry about it, you got the part."
It took a group of around 100 people three years to complete this movie. For one second of film, up to 12 stop-motion moves had to be made.
Joe Ranft: Igor, Dr. Finkelstein's assistant when he gives him the plans to create the skeleton reindeer. He appears in several scenes in the film but had only one line.