The movie is based on the second and third of L. Frank Baum's Oz books: "The Marvelous Land of Oz" and "Ozma of Oz". Elements from the former include the introduction of Jack Pumpkinhead, the witch Mombi and her powder of life, the conquest of the Emerald City, the escape by flying sofa, and the search for Princess Ozma. From the latter comes the return of Dorothy, the talking chicken Billina, the Wheelers, the discovery of Tik-Tok, a princess with interchangeable heads, the introduction of the Nome King, and the ornament room.
Cartoonist Tim Burton has acknowledged Jack Pumpkinhead as an inspiration for the iconic character Jack Skellington in L'Étrange Noël de monsieur Jack (1993).
Disney actually fired director Walter Murch about a week into production due to budget concerns. The studio found dailies lacking and Murch's slow shooting pace disheartening. Murch contacted friends Francis Ford Coppola, Steven Spielberg and George Lucas for help, and all three directors lobbied Disney to rehire Murch. Lucas even offered to take over directing himself should Murch fall behind schedule. Murch finished the film on schedule, though while in post-production studio management changed. The new executives had little faith in the movie, and doomed it with limited promotion and a short theatrical run.
Fairuza Balk's ruby slippers were specially handmade with imitation rubies and rotoscoped in post-production to give them a magical look. The rubies were actually glass beads imported from Austria and individually attached to the shoes with a special spray adhesive. This later proved problematic, as the hot stage lights melted the adhesive, and the young actress's fidgety movements would often knock the beads off. Tired of chasing after detached beads, the wardrobe staff finally ordered the shoes to be worn only when visible on camera. Balk confirmed to a fan, via Twitter in September of 2017, that she got to keep one pair of the ruby slippers she wore in the film.
Fairuza Balk: [witches] This is one of several Fairuza Balk movies which involve witches. Others include The Worst Witch (1986) and Dangereuse Alliance (1996).