It’s true what they say — the years start coming and they really don’t stop coming. It has been almost 20 years since America’s favorite green ogre, Shrek, made his debut on movie screens across the world. We have never been the same.

Shrek is a modern classic. But while the movie and its many (five!) iterations secured top spots in animation history, that almost wasn’t so. Many surprising factors complicated the production process, making it a miracle that DreamWorks even completed the project. Let’s examine the many onion like layers to our dear ogre.

1. DreamWorks animators were so committed to getting the CGI in Shrek right, they took mudbaths to study the visual of the now famous scene where Shrek takes a mudshower in his swamp.

DreamWorks Animation

2. Shrek was based on a children’s book published in 1990. William Steig based his Shrek on 1940s wrestler Maurice Tillet; he had acromegaly, a condition that causes bones to overgrow and thicken, and was used for visual inspiration in constructing the ogre we know.

Wikimedia Commons

3. None other than Steven Spielberg bought the rights to Steig’s novel just a year after the book was released. He knew he wanted to make a movie version, but actually getting the film made would present tons of setbacks.

Gage Skidmore / Flickr

4. Spielberg had so much trouble getting the Shrek script picked up, he founded his own animation studio to make it happen. After teaming up with David Geffen and Jeffery Katzenberg, DreamWorks Animation was founded in 1994.

Robert Durell / LA Times

5. We know that our fav Shrek and donkey duo is voiced by Mike Myers and Eddie Murphy, respectively. But, initially the role of Shrek was going to be given to Bill Murray and that of donkey to Steve Martin.

DreamWorks Animation

6. Incredibly, Mike Myers wasn’t even second in line to voice Shrek. Comedian Chris Farley had recorded more than half of the ogre’s lines before his tragic death in 1997. Like Farley, the original Shrek was more lovable and looked totally different.

7. Smash Mouth’s hit “All Star” is synonymous with the movie, but it almost did not make the final cut. It was originally put in as a placeholder, but tested so well with focus groups that they kept the song in.

SMASH MOUTH / Youtube

8. When Mike Myers finally got around to recording his lines as Shrek, he decided he needed an accent to create the character. He tested out British and even Canadian accents before he tried the guttural Scottish tongue of Shrek that made it into the movie.

DreamWorks TV / Youtube

9. Perry, a miniature donkey from Palo Alto, California, was the real-life inspiration for the absolutely lovable sidekick to Shrek. We didn’t know we needed a donkey voiced by Eddie Murphy until we had it.

Greypo / Reddit

10. While visually very different, Princess Fiona and her voice, Cameron Diaz have a lot in common. In fact, the famous scene where Fiona burps in front of Shrek is inspired by a real-life incident where Diaz burped in front of the director.

11. The CGI utilized in the creation of Shrek was without a doubt some of the most advanced and celebrated of the time, but executives weren’t even planning on using it at first. They were going to use stop-motion to film the movie.

DreamWorks Animation

12. Based on all the offers that preceded his, it’s crazy that Myers ever got to play Shrek because yet another celebrity turned down the role: When Nicholas Cage was offered the part, he declined because he didn’t want to be associated with an ogre.

13. Shrek was popular with children and adults because the script was written to make people of all ages laugh. The many pop culture references and veiled adult subjects entertain adults who might be watching the animated movie with their kids. It raised the bar.

DreamWorks Animation

14. When Shrek came out in 2001, it wasn’t common for animated films to be lauded by critics. But, famed movie critic Roger Ebert didn’t hide his love for the movie, stating “Shrek is jolly and wicked, filled with sly invokes and yet somehow possessing a heart.”

WikiCommons

15. In 2001, the Academy Awards opened up a category for Best Animated Film because of the unprecedented competition DreamWorks provided for Disney. That same year, Shrek won the Oscar for Best Animated Feature.

16. John Lithgow voiced Lord Farquaad, the pint-sized pain in the ass who almost snagged Fiona from Shrek, in the original film. Lithgow, who is 6’4, said he would never play a short character, but changed his mind once he read the script.

17. Jeffrey Katzenburg was a Disney executive before he jumped ship to co-found DreamWorks. It has been rumored that Katzenburg modeled the villainous Lord Farquaad after his former Disney boss, Michael Eisner.

DreamWorks Entertainment

18. If you look closely, the dance performed by Robin Hood’s Merry Men in the movie might look familiar. That’s because the animators had the men dance the actual choreography from the famed touring group Riverdance.

DreamWorks Animation

19. The name Shrek was no accident. It is based off of the German word “schreck,” which translates to “fear.” It’s also used as slang for “monster.” True fans know that his gruff appearance is not indicative of his ultimately warm heart.

20. After the success of the first film, Spielberg thanked the cast for what they did to make his idea come to life. Surely, Disney execs kicked themselves for not thinking of this first. Of course, executives there faced some serious drama over the years, too.

Laurie Curtis / Flickr

Disney has been going the extra mile to entertain for decades. Before Snow White and the Seven Dwarves (1937) hit cinemas, the world had never seen a hand-drawn animated feature film. To fund production, Walt had to mortgage his house!

2. Pinocchio (1940): Walt loved slapstick and pushed the producers to include as many visual gags as possible: with incentive! Depending on the strength of your gag, you could earn anywhere from $5 to $25. Sometimes it pays to be silly!

Pinocchio

3. Dumbo (1941): This film was such a phenomenon that TIME Magazine planned to honor the fictional elephant with the title of “Mammal of the Year” in 1941. The attack on Pearl Harbor scrapped those plans, though, and TIME gave the usual “Man of the Year” award to Franklin Delano Roosevelt instead.

4. Cinderella (1950): In a decision to cut costs, the producers of this classic fairytale shot the entire movie first in live-action, then traced over the footage. Some animators enjoyed the time saver, but others weren’t thrilled to be limited by pre-shot footage.

5. Fantasia (1940): The first film to ever feature a Pegasus on screen, Fantasia left the animators with an unusual dilemma: what would a flying horse would do with its legs as it flew? The standard they set defined how the mythical beast appeared in films for decades.

Fantasia

6. Dumbo (1941): The story of the elephant circus performer held a special place in Walt’s heart. It remained his favorite Disney film until the day he died: “We weren’t restricted by any set storyline,” he said, “so we could give our imaginations full play.”

7. Alice in Wonderland (1951): Though it was released in 1951, work began on initial drafts of Alice back in 1933. Disney’s first iteration debuted as a short film in 1936 as Thru the Mirror and starred none other than Mickey Mouse himself.

8. Snow White and the Seven Dwarves (1937): Back in 1934, producers had ideas for over 50 dwarves with distinct personalities before narrowing it down to seven. Some of the rejected candidates? Burpy, Gaspy, Sniffy, Goopy, and Biggy-Wiggy.

9. Pinocchio (1940): The story about a puppet brought to life wasn’t supposed to be Disney’s second animated feature. Bambi was originally intended to be number two, but animators ran into so much trouble making the deers’ motions realistic that it wasn’t released for another two years.

Pinocchio

10. Bambi (1942): Felix Salten, the author of the novel Bambi is based on, sold the film rights for just $1,000. It turned out to be a bargain for Disney when the film raked in $267.4 million at the box office.

11. Cinderella (1950): Kendall O’Connor, one of the artists behind the film, used his wife Mary Alice as inspiration to create the Fairy Godmother. Off-screen, Mary Alice was a widely adored pillar of their community and was dubbed the “Fairy Godmother of Burbank.”

12. Fantasia (1940): Disney’s magical symphony wasn’t just groundbreaking for its technical and artistic feats; it also cemented Mickey Mouse’s now-familiar design for the next 80 years. The most notable upgrade from his previous model? Pupils!

13. Peter Pan (1953): Producers struggled to find the perfect sound for Tinkerbell’s wings and tried countless kinds of bells and chimes without success. Surprisingly, the sound they liked the best was made by pieces of aluminum strung together.

Rider University

14. Dumbo (1941): Dumbo’s almost-psychedelic dream sequence led many to wonder if the animators had created the scene under the influence of some substance. But the team said working at Disney trained them to expand their imaginations without assistance.

Dumbo

15. Peter Pan (1953): Contrary to a popular myth, Marilyn Monroe was not the model for Tinkerbell in Peter Pan. Instead, the filmmakers used footage of another actress, Margaret Kerry, to get inspiration for the feisty fairy.

16. Alice in Wonderland (1951): This classic’s jam packed with 15 songs — more than any other Disney feature to date. Twelve additional songs were written but not used in the film, including one starring Humpty Dumpty.

17. Peter Pan (1953): Walt always felt a close connection to Peter Pan, and for a good reason — he’s the only character Walt ever portrayed on stage! A young Walt once smashed open his piggy bank for money to see a touring company perform the play, which inspired him to join his school’s production.

18. Snow White and the Seven Dwarves (1937): Snow White isn’t just Disney royalty, she’s one of the few fictional characters to have a star on the Hollywood Walk of Fame. Turns out wishing on a star actually works!

19. Fantasia (1940): Early on, Disney animators used live action recreations of scenes to figure out how to get the motions just right. Footage of a football player knocking down barrels inspired a scene where Mickey tries to subdue a rampaging broom.

20. Bambi (1942): “Man” is the unnamed villain in Bambi, but Walt originally planned for the hunter to meet a much darker end. In the first draft of the film, he was burned alive in the forest fire he accidentally caused. Yikes!

While Disney might feel like magic, the animators and producers make sure to get their facts straight. Some details that seem completely farfetched are actually rooted in reality.

1. The Fire Extinguisher Scene in WALL-E: During the part in which WALL-E and Eve dance in space, WALL-E is seen using a fire extinguisher to move around in zero gravity. When asked if this was a realistic use of the device, astronaut Roberta Clark confirmed that it was totally possible (and totally awesome).

2. The Shipwreck in The Little Mermaid: At the beginning of the film, we follow Ariel as she explores a sunken ship. According to a maritime expert at Texas A&M University, both the build of the ship – a Spanish galleon – and the timeline at which it deteriorated, were completely accurate.

3. Elsa’s Iciness in Frozen: Ice-queen powers aside, the real reason Elsa was always so cold in the film could’ve been due to her social isolation. Studies have found that social exclusion and loneliness may actually cause a person to feel colder than those who interact often with others. I guess the cold did bother her…

4. Roar Practice in The Lion King: While it may have seemed silly for Simba to work on his roar, the slight variations in a lion’s vocalization can mean the difference between a simple greeting and a challenge for dominance. No wonder Simba had to work so hard to make sure his roar was just right!

5. Pilot Lingo in The Incredibles: During the scene where Elastigirl flies a plane, she uses real terminology when talking over the radio. Director Brad Bird said that Holly Hunter, who is the voice of Elastigirl, was adamant about learning the proper lingo.

6. Memories in Inside Out: The human mind isn’t full of animated characters, but the film wasn’t too far off in illustrating how memories function. Individual neurons in the brain recall memories in response to audio and visual cues, allowing us to re-experience certain past emotions in the present.

7. Marlin’s Journey in Finding Nemo: It’s safe to say that any parent would swim the ocean to find their lost child, but Marlin’s journey was actually not that uncommon. In reality, baby clownfish will often travel hundreds of miles across the sea to join up with other clownfish.

There’s another slice of life scene in this movie, too. When Marlin and Dory ride the EAC (East Australian Current) alongside the lovable sea turtles, Crush and Squirt, they’re actually mimicking a what lot of fish do in order to travel long distances faster.

8. Chief Tui’s Tattoo in Moana: In Samoan tradition, any man who wanted to be a Matai, or chief, was required to get a pe’a tattoo. This tattoo denotes a man of great importance; it’s no wonder, then, that Moana’s father had one.

9. Kitchen Scenes in Ratatouille: According to a number of French chefs and food experts, the film’s portrayal of life in a high-end restaurant was spot on. Pixar spent time researching sounds and movements in French kitchens to get the film just right.

10. Wasabi’s Plasma Board in Big Hero 6: The board that Wasabi uses to slice paper-thin apples may seem like science fiction, but in reality, this technology is already being used. Many microsurgeries are conducted using tiny plasma needles.

11. Punishment in The Emperor’s New Groove: Being thrown out the window might seem absurd, but it’s actually not. This was a common practice in Incan time, where gruesome punishments discouraged repeat offenders.

12. Night Howlers in Zootopia: The strange flower that turns animals “savage” in the film is actually based on the autumn crocus. Though it won’t necessarily drive the eater to madness, devouring any part of this flower may cause cardiac arrest in humans, and even deadlier effects in animals.

13. The Ammunition in Pirates of the Caribbean: In The Curse of the Black Pearl, the ammunition fired was based on the kind found on the wreckage of Blackbeard’s ship. According to scholars, pirates would fire glass, metal shards, and even utensils in an effort to preserve an enemy ship for capture.

14. Food Theft in A Bug’s Life: While Hopper and his gang were made out to be the bad guys, there’s another scarier insect: the butterfly. Rather than take food by force, butterfly larvae emit the same scent that ants do, tricking the ants into feeding and caring for them.

15. The Beasts in Hercules: The enemies Hercules defeats during the “Zero to Hero” montage are taken straight from the mythical figure’s 12 Labors. In the film, Hercules conquers the Nemean Lion, the Erymanthean Boar, and the Stymphlaian Birds.

16. Go Go’s Maglev Disks in Big Hero 6: Another true-to-life gadget used by one of the film’s heroes are these disks, whose technology is already being implemented by Japan’s frictionless maglev train. In the U.S., a train like this could travel from New York to Los Angeles in just seven hours!

17. The Biscuits in Brave: Pixar is known for its attention to even the smallest of details, and in this film, even the biscuits that Merida and her brothers try to steal are historically accurate. Known as Tipperary biscuits, these traditional Scottish sweets are made with spice, strawberry jam, and a cherry on top.

18. White Tunics in The Hunchback of Notre Dame: Those who committed crimes in Medieval Europe could “claim sanctuary” by staying with a church in order to avoid prosecution. To indicate their sanctuary status, the criminal would dress in a simple tunic with no hat or shoes, much like Phoebus and Esmerelda did at the end of the film.

19. Percy in Pocahontas: No, Percy wasn’t a real dog, but it was pretty common for nobles of the Victorian Era to carry around their pooches. At the time, parading a dog around like Governor Ratcliff did with Percy was considered to be a visible demonstration of man’s dominion over nature.