Some theories on The Wizard of Oz

The Wicked Witch of the West was deemed too scary after the public screening and MGM had to cut out the most evil bits.

There were actually three Totos. Two were real, cat chasing dogs. The third was a stuffed animal used in the poppy field scene. The real Totos adored Dorothy and risked their lives for her.

There had been four directors by the time filming was complete.

MGM also cut some of Totos scenes: he was becoming the star and leaving Judy Garland in the shadows.

The munchkins heights ranged from 2'3" to 4'8". They regard anyone over 5' tall as big people.

The munchkin involved in the extinguishing the witch is Billy Curtis. He drove a full sized car and would take Judy Garland to meet David Rose at the ice-skating rink each night. Judy Garland did not remember Billy Curtis though.

Each main character in Oz represents a character in Dorothy's Kansas life - Mira Gulch = Wicked Witch of The West.
However Glinda, the Good Witch of the North has no Kansas character.

Garland had her teeth fixed for the film. They have been likened to the picket fence around her Aunt and Uncle's farm.

The horses in Oz were all painted different colours. The effects people used Jell-O which was nice but problematic in that the horses kept licking it off between scenes.

Toto was scared of the horses, being more of a coward than the lion.

Professor Marvel's coat was bought from a second hand shop by the wardrobe man. It was black broadcloth with a velvet collar. During filming one day, the Professor turns the pockets out and on one is written L.Frank Baum.

During the first scenes after Dorothy's arrival in Oz, whilst singing Ding Dong the Witch is Dead there is one, very tall, female munchkin doing her utmost to be noticed and doing just that.