Trivia

Judy Garland found it difficult to be afraid of Margaret Hamilton, because she was such a nice lady off-camera.

Many shots were trimmed down or edited out of the film because they were too intense for families and children. In particular, one deleted shot shows the tornado completely enveloping the farmhouse. Also, later in the film a lot of The Wicked Witch of the West's scenes were either trimmed or deleted entirely, as Margaret Hamilton's performance was thought to be too frightening for audiences.

When the wardrobe department was looking for a coat for Frank Morgan (Professor Marvel/The Wizard), it decided it wanted one that looked like it had once been elegant but had since "gone to seed". They visited a second-hand store and purchased an entire rack of coats, from which Morgan, the head of the wardrobe department and director Victor Fleming, chose one they felt gave off the perfect appearance of "shabby gentility". One day, while he was on set in it, he idly turned out one of the pockets and discovered a label indicating that it had been made for L. Frank Baum. Mary Mayer, a unit publicist for the film, contacted the tailor and Baum's widow, who both verified that it had at one time been owned by the author of the original "Wizard of Oz" books. After the filming was completed, it was presented to Mrs. Baum.

Margaret Hamilton, a lifelong fan of the "Oz" books, was ecstatic when she learned the producers were considering her for a part in the film. When she phoned her agent to find out what role she was up for, her agent simply replied, "The witch, who else?"

The iconic ruby slippers are now at the Smithsonian Institution's National Museum of American History, and so popular that the carpet in front of them has had to be replaced numerous times due to wear and tear.