On June 12, 1981—35 years ago today—Mel Brooks’s irreverent take on the course of human events opened in theaters. Though critics were thoroughly divided, History of the World, Part 1 grossed a respectable $31.6 million at the box office, and left countless viewers hungry for a sequel. These 11 footnotes should get you ready for a 35th anniversary screening.

1. ORSON WELLES BREEZED THROUGH HIS LINES.

History of the World, Part 1 opens in a deceptively dramatic fashion. As we witness the very dawn of our species, a commanding voice declares “And the ape stood, and became man.” This unforgettable baritone belonged to Orson Welles. Brooks hired him to narrate the five major segments that make up the film.

Beforehand, it was agreed that the cinema legend would receive $5000 per day in exchange for his services. Figuring that he’d have to spend five eight-hour days recording and re-recording these lines with Welles, Brooks paid him $25,000 up front. But by noon on the first day, Welles had recorded every single one of his lines to perfection. “Oh my god, I could’ve paid you $5000,” Brooks lamented. After kicking himself for a few minutes, the funnyman asked Welles how he planned to spend the bounty. “Cuban cigars and sevruga caviar,” the Citizen Kane director replied.

2. THE LEAD CAVEMAN WAS PLAYED BY MEL BROOKS’S FORMER BOSS.

In 1949, the late, great Sid Caesar hired Brooks as a joke writer for The Admiral Broadway Revue, a short-lived NBC variety show. After the series ended, Brooks joined the staff of Caesar’s next program, Your Show of Shows. Working for a living legend was something the younger man would never forget. Even today, when Brooks is asked about his mentor, he often says “No Sid Caesar, no Mel Brooks.”

Twenty-two years after Your Show of Shows ended its run, Brooks expressed his gratitude to Caesar by giving him a major role in 1976’s Silent Movie. Brooks would cast the comic again in History of the World, this time as Chief Caveman, who has a zeal for music (and slapstick).

3. ACCORDING TO BROOKS, THE MOSES SCENE WAS A LAST-MINUTE ADDITION.

“Sometimes, you will get very lucky and the set will give you ideas for jokes,” Brooks said in a 2012 interview with the Directors Guild of America. One day, he was gazing out at the scenery that had been built for the caveman segments in History of the World when the gears in his head started turning. “I immediately thought, ‘Well, where do I go from here?’” Brooks recalled. Heading into the shoot, his plan was to “skip the Bible and go to Rome.’” But eventually, he realized that the Stone Age set might enable him to explore another chapter in world history. With a few minor alterations, Brooks converted his faux caves into a mountaintop, and the Moses bit was born.

4. ORIGINALLY, JOSEPHUS WAS GOING TO BE PLAYED BY RICHARD PRYOR.

Josephus, a quick-witted Ethiopian slave, is a principal character in the film’s Roman Empire segment. Richard Pryor seemed perfect for the part and, to Brooks’s delight, he accepted the role. Unfortunately, though, a terrible accident kept him out of the movie. On June 9, 1980, less than a month after History of the World began production, the comic lit himself ablaze while freebasing cocaine and had to be hospitalized. At the suggestion of Madeline Kahn (who played Empress Nympho), Brooks handed the role to tap dancer Gregory Hines.

5. TO PLAY COMICUS, THE “STAND-UP PHILOSOPHER,” BROOKS TOOK SOME CUES FROM EDDIE CANTOR.

Eddie Cantor was one of Brooks’s personal heroes. An actor, singer, comedian, and radio personality, Cantor’s talents were almost limitless. When Brooks cast himself as Comicus in History of the World, he proceeded to copy some of his idol’s manic facial expressions. “I made my eyes pop out in reactions, like he did,” Brooks says. “My Comicus was a tribute to Eddie Cantor. He was my timing, my excitement.” Even the character’s wardrobe, a “short little toga,” was modeled after the outfit Cantor wore in Roman Scandals, a 1933 musical comedy.

6. A LONGTIME PARTNER HELPED BROOKS WRITE THE MOVIE’S BIG SHOWSTOPPER

Ronny Graham and Mel Brooks first crossed paths as castmates in the hit Broadway revue New Faces of 1952, for which they co-wrote several skits. “[We] became fast friends,” Brooks said. Once Brooks decided that History of the World needed a Busby Berkeley-style musical number about medieval torture, he immediately reached out to Graham, who happened to be a successful musician.

“Together we began a fierce collaboration on a song called ‘The Inquisition,” Brooks recalled. The rest is, well, history. In the final film, Brooks takes center stage during this segment, hamming it up as the grand inquisitor Torquemada. Meanwhile, Graham makes a cameo as one of the Jewish prisoners.

7. ONE DELETED SCENE INVOLVED A NUCLEAR MISHAP.

Little is known about this segment. In an interview with film critic Gene Siskel, Brooks revealed that he’d filmed a brief scene that made light of the notorious Three Mile Island incident. “I had a father and a mother made up to look like half a dog and half a cat as a result of a nuclear meltdown,” Brooks told Siskel. When test audiences reacted poorly, this bit was removed. However, at least one journalist managed to see an extended cut which contained the footage. In his (lukewarm) review of History of the World for The Washington Post, critic Gary Arnold wrote, “there’s a routine about Three Mile Island that’s almost awesome in its lack of comic point.”

8. BROOKS HAD HIS DOUBTS ABOUT THE INQUISITION NUMBER.

In general, Brooks’ films aren’t exactly noted for their political correctness—after all, the director’s very first film was about an Adolf Hitler musical. Still, even he wondered if the breakout song in History of the World had finally crossed a line. “I don’t know how audiences are going to react to the Spanish Inquisition sequence,” Brooks told Mademoiselle. As he put it, trying to get a laugh out of any scene that involved “Jews on racks” could be “very dangerous.” In the end, history repeated itself. After The Producers was released, Jewish leaders contacted Brooks en masse with complaints about the film’s brazen Nazi gags. Thanks to that big inquisition number, History of the World, Part 1 garnered a similar reaction. “I got a lot of write-ins from rabbis,” Brooks admitted.

To those who’d written him, Brooks replied, “I’m just mentioning [the Inquisition] so people don’t forget!” Echoing his defense of both The Producers and Blazing Saddles, he went on to argue that satire could be an effective weapon against bigotry. While speaking about History of the World in 1982, Brooks said “Comedy brings religious persecutors, dictators and tyrants to their knees faster than any other medium.”

9. KING LOUIS’S SCENES WERE FILMED AT AN ENGLISH PALACE.

It’s good to be the king, but language barriers aren’t much fun. Feeling that it’d be easier to shoot the French revolution chapter in English-speaking countries, Brooks chose Blenheim Palace as a stand-in for Versailles. Built in the early 18th century, Blenheim is where the Duke of Marlborough has historically resided. An architectural beauty, the palace has also made appearances in such films as The Libertine (2004) and Mission Impossible: Rogue Nation (2015) [PDF].

10. HISTORY OF THE WORLD CAME WITH A STEEP PRICE TAG—AT LEAST FOR A MEL BROOKS PROJECT.

Brooks himself claimed that History of the World’s budget—an estimated $11 million—exceeded that of his previous three films combined. Particularly expensive was the Inquisition scene, in which the set alone cost $1 million. By comparison, the entire budget of 1968’s The Producers was a paltry $941,000.

11. BROOKS NEVER INTENDED TO MAKE A SEQUEL.

With a title like History of the World, Part 1, you’d assume that a Part 2 would be hot on its heels. But Brooks has stated that he never intended to make a sequel. On June 7, 1981—just four days before the movie opened in theaters, the director weighed in on this subject in The New York Times. “Will there be a History of the World, Part 2?" he asked, rhetorically. “No. Maybe a Part 4, never a Part 2."

The misleading title—as he later put it—was meant as “a joke,” one he now regrets. “I’m sorry I did that, the kids keep writing me letters asking when we are going to see part two,” he explained while promoting his DVD box set, The Incredible Mel Brooks: An Irresistible Collection of Unhinged Comedy. Still, he’s definitely thought about what new topics he might spoof in a potential follow-up—as he states in the below clip. “There’s a lot of things I haven’t covered in history. Things like the Civil War.”