At the height of the Second World War, Humphrey Bogart and Ingrid Bergman joined forces for one of the greatest movies ever made – ranked by some publications as literally the greatest movie ever madeCasablanca, a wartime love story that transcends its setting with timeless storytelling.

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No one involved in the making of Casablanca expected it to be a success, despite its A-list stars, but it enjoyed a solid performance at the box office and, more importantly, was praised by critics as a masterpiece and won the Academy Award for Best Picture. Since WWII was ongoing at the time, Casablanca endured a tricky production.

Casablanca Was Based On An Unproduced Play

Humphrey Bogart sitting in a bar in Casablanca

In 1940, prior to U.S. forces’ entry into World War II, Murray Burnett and Joan Alison wrote a play called Everybody Comes to Rick’s with an anti-Nazi, pro-French Resistance message, but it was never produced.

Warner Bros. bought the rights to the unproduced play for a record-breaking $20,000 (worth over $370,000 today, adjusted for inflation) and turned it into Casablanca.

Clark Gable And Rita Hayworth Were The First Choices For Rick And Ilsa

Rhett Butler looking up the stairs in Gone with the Wind

Joan Alison, co-writer of the unproduced play upon which Casablanca was based, always envisioned Clark Gable as Rick. She didn’t care for Humphrey Bogart, seeing him as “a common drunk.” An early press release claimed Ronald Reagan had been cast as Rick, but this is believed to have been a hoax to promote his movie Kings Row.

Rita Hayworth was the original choice to play Ilsa before the great Ingrid Bergman was cast. Joseph Cotten was considered for the role of Victor Lazlow, while Otto Preminger was considered for the role of Major Strasser.

Most Of The Sets Were Recycled From Previous Movies

Casablanca

Rick’s Café was one of the only sets that got built from scratch for the production of Casablanca.

The movie primarily recycled sets from previous Warner Bros. productions, because World War II had caused a shortage of building supplies.

Howard Hawks Turned Down The Chance To Direct

John Wayne stands with two other men in Rio Bravo.

Producer Hal B. Wallis’ top choice to direct Casablanca was William Wyler, who would go on to helm such masterpieces as Ben-Hur and Roman Holiday, but the director’s chair ended up being taken by Michael Curtiz.

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The job was also offered to Howard Hawks, the master filmmaker behind Rio Bravo, His Girl Friday, and the original Scarface, but he turned it down in order to direct Sergeant York instead.

The Script Was Written During Filming

Rick, Ilsa, and Sam in Casablanca

The cast and crew began shooting Casablanca without a complete script. The script was written during production, with elements being changed to suit the Hays Code. The source material ended with Rick and Ilsa leaving for America, but the Hays Code wouldn’t allow movies to depict characters getting away with adultery.

It took the writers a long time to come up with an ending that everyone was happy with. They ended up reverse-engineering it from the line “Round up the usual suspects,” which the filmmakers liked.

Humphrey Bogart Had To Wear Platform Shoes Next To Ingrid Bergman

Humphrey Bogart and Ingrid Bergman in Casablanca

Height differences between actors is still something that films are dealing with, and even Casablanca had to do something about its stars and how tall they are.

Since Humphrey Bogart was a fair amount shorter than Ingrid Bergman, he had to wear platform shoes in shots where he was standing next to her.

There Are Many Rumors About The Origin Of “Here’s Looking At You, Kid”

Rick says 'Here's looking at you, kid' to Ilsa at the end of Casablanca

There are a few rumors about the origin of the line “Here’s looking at you, kid.” The most common one is that it was improvised, but it’s been confirmed to predate both this movie and Bogart’s previous acting work.

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In 1932, a decade before Casablanca was made, Eddie Cantor wrote, “Here’s looking at you, Sid,” on his star outside Grauman’s Chinese Theater, in reference to the theater’s owner, Sid Grauman. Cantor meant it as a play on “Here’s looking at you, kid,” which was apparently a popular phrase at the time.

A Lot Of The Nazis Were Played By German Jews Who Escaped The Nazis

The Nazis in Casablanca

While Casablanca was being shot, the Second World War was raging on.

A lot of the Nazis that appear in the movie were, ironically, played by German Jews who had escaped from Nazi Germany.

Humphrey Bogart’s Wife Thought He Was Having An Affair With Ingrid Bergman

Rick and Ilsa in Casablanca

Humphrey Bogart’s wife Mayo Methot was entirely convinced that he was having an affair with his co-star Ingrid Bergman. She’d regularly confront him about it in his dressing room before shooting, so he often came to the set in a bad mood, which fed into the character.

Despite Bogart and Bergman’s on-screen chemistry, they didn’t actually spend much time together off-camera. The only time they ever got along was when they had lunch with Geraldine Fitzgerald, who said they both thought the movie would suck.

The Filmmakers Couldn’t Shoot At An Airport After Dark

The airport finale in Casablanca

The ending of Casablanca had be shot on a soundstage made up to look like an airport runway, because the ongoing Second World War prevented the filmmakers from being able to shoot at an airport after dark, due to security concerns.

The airplane that appears in the background is a cardboard cutout made to look like a plane using forced perspective. A similar technique was later used for the “space jockey” scene in Ridley Scott’s Alien.

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