The Wizard of Oz had its Hollywood premiere on August 16, 1939, which means the classic is celebrating its 75th anniversary today.

By now you probably know this amazing film was originally a loss for MGM and that Toto the dog was paid more than the Munchkins. You may also know that the Scarecrow said the incorrect Pythagorean Theorem or that the book was based off the United States banking crisis. But even if you’re in love with the film, we bet you didn’t know the following seven facts:

1. Judy Garland’s iconic rendition of Over the Rainbow was almost cut from the film entirely.

The song was almost taken out of the film on multiple occasions. Originally when composer Harold Arlen presented the song, it was thought to be to “symphonic” and that it would have to be sung like an opera. Arlen simplified the melody with smaller chords and the scene was created. Then director Victor Fleming thought it should be cut “because it’s too long and it’s too difficult.” The songwriters, Arlen and lyricist Yip Harburg, convinced MGM it should go back in. Another director, one of the five who worked on the film, cut it back out. MGM also may have thought it was problematic to have their star singing in a farmyard.

In the end, Arlen and Harburg convinced MGM to insert the song back into the final release. But trouble didn’t end there. At the time, many critics deemed Over the Rainbow long and unnecessary. Among many other journalists, Robbin Coons of the Associated Press said, “The picture could have been speeded more at its beginnings, especially by the elimination of Judy’s first song.” As you may know, Over the Rainbow ended up winning the Academy Award for Best Original Song.

2. Director Victor Fleming slapped Judy Garland when she wouldn’t stop giggling. Then she kissed him.

In Victor Fleming: An American Movie Master, Michael Sragow wrote about the incident:

When [Judy] Garland couldn’t stop breaking into giggles at the pseudo-menacing advance of [Bert] Lahr’s Cowardly Lion, Fleming escorted her off the Yellow Brick Road, said, ‘Now darling, this is serious,’ slapped her on the cheek, then ordered, ‘Now go in there and work.’

Apparently Victor Fleming felt really terrible about slapping Judy Garland after the incident and started saying that somebody on the crew should punch him. Garland overheard this and said, “I won’t do that, but I’ll kiss your nose.” And then she did.

3. Multiple lead actors were physically scarred due to special effects and costuming used in the film.

While filming her exit from “Munchkinland,” Margaret Hamilton, the actress who played the Wicked Witch of the West, received severe burns on both her face and hands. The fire she was supposed to be leaving through accidentally rose up before she had descended. Hamilton’s stunt double was also burned while filming a different scene when a pipe exploded.

Ray Bolger, the actor who played the Scarecrow, ended up having “permanent” lines on his face due to the intense rubber mask that was glued to his face every morning for filming.

A different actor, Buddy Ebsen, was actually supposed to play the Tin Man, but then his lungs failed. The original costume for Tin Man involved covering Ebsen in aluminium dust which ended up sending him to the hospital for two weeks.

Also, the temperatures on set were also insanely hot due to the technicolor process requiring very bright shots. Cinematographer Harold Rosson claimed “people were always fainting and being carried off the set,” due to the heat.

4. The green makeup was so toxic that Margaret Hamilton wasn’t allowed to handle food and had to be specially fed.

The makeup put on Hamilton was copper-based and therefore could be toxic if ingested. The makeup person for Hamilton, Jack Young, explained the risk:

... green is toxic because it’s made with copper. Every night when I was taking off the Witch’s makeup, I would make sure that her face was thoroughly clean. Spotlessly clean. Because you don’t take chances with green.

Apparently, the colouring stained her face for quite some time after filming wrapped.

5. But not all costumes were toxic. The Tin Man’s “oil” was chocolate sauce and the horses were covered in “Jell-O.”

Jack Haley, the actor who played the Tin Man explained the fake oil: “The oil Ray Bolger squirted at me, to loosen up my joints, was not oil but chocolate syrup. They squirted chocolate in my face, because the oil wouldn’t photograph right, but chocolate will.”

The horse that kept changing colours was actually played by four horses. Each were covered in lemon, cherry or grape powdered gelatine. The horse apparently kept trying to lick the gelatine off. This may seem particularly cruel as common wisdom is that gelatine comes from horse hoofs and bones. In fact, the powder is mostly made from cows and pigs.

6. Professor Marvel’s jacket was bought from a thrift store. In the most insane coincidence ever, the jacket used to belong to L. Frank Baum, the author of the original novel.

The truthfulness of this is a bit up in the air, but it has been somewhat confirmed by Harold Rosson, the previously mentioned cinematographer and a publicist for the film at the time. Apparently, the crew wanted a ratty, but once expensive jacket for the character of Professor Marvel to wear in the film. They went to a thrift store and the jacket they ended up choosing was later discovered to once be owned by L. Frank Baum. Someone noticed that his name was stitched into the jacket after it was chosen.

7. The Wizard of Oz is the most watched film of all time.

This, according to the Library of Congress. A bonus 7.5 fact for the 75th anniversary ... if you’re a super fan, you’re certainly not walking the yellow brick road alone!

This article is republished with permission from the Huffington Post.