The movie was set to be filmed at the University of Missouri until the president of the school read the script and refused permission. It was filmed at and around the University of Oregon in Eugene instead.
The President of the University of Oregon only allowed this movie to be filmed on that campus because he decided he did not know how to read screenplays. In 1967 he had received the screenplay for a movie but had denied it permission to film there. That movie was The Graduate and he liked that movie so much that he decided he didn't want to miss another opportunity, so he allowed Animal House to be filmed on the University of Oregon campus. But he insisted that the college's name not be listed in the film's credits.
The movie concludes by describing each character's fate. Niedermeyer was "killed in Vietnam by his own troops." In director John Landis' segment of Twilight Zone: The Movie, some soldiers are overheard discussing "fragging Niedermeyer."
Babs becomes a tour guide at Universal Studios. The credits for this and other John Landis films contain an advertisement for a tour at Universal Studios. The ad says, "Ask for Babs." As of 1989, Universal Studios no longer honors the "Ask for Babs" promotion, which was either a discount or a free entry.
Donald Sutherland was so convinced of the movie's lack of potential, that, when offered a percent of the gross or a flat fee of $75,000 for his three days' work, he took the upfront payment. Had he taken the gross percentage he would have been worth an additional $3-4 million.
The interior scenes of the Delta house were filmed in a Sigma Nu fraternity. The exterior of the Delta house was a dilapidated house from the 1800's that was torn down in the mid 80's. The sorority house's exterior is the real exterior of the Sigma Nu house that was used for the interior scenes.
John Landis had a budget of only $2.5 million, so to cut costs the movie was shot almost entirely on the U of O campus, including the court scene and scenes in the dean's office (the exceptions being the road trip and the parade, which were filmed near Cottage Grove, Oregon).
The University of Oregon reluctantly allowed its campus to be used and gave the crew 30 days to complete filming. This meant that the cast and crew faced six-day work weeks and completed shooting with only two days to spare.
Although the film takes place in Pennsylvania, a Tennessee flag is shown in the courtroom. This is because the set decorator was unable to find a large enough Pennsylvania flag for the scene, and the blue Oregon state flag wouldn't work because it had "State of Oregon" text on the upper part. So the set decorator used the most generic flag he could find, which turned out to be the Tennessee state flag.
One bit that was written in the original script but never filmed included a parade bust that was destroyed at the climax of the film. The bust was of John F. Kennedy, the US President in 1962, and the gag was Kennedy's head was punctured in the same way the real Kennedy would be shot the next year. Director John Landis cut the idea because he felt the tone of the gag was wrong.
The noble brass theme heard when the Faber campus is first shown is an excerpt from Johannes Brahms' "Academic Festival Overture". This melody is based on a German student drinking song called "We have built a stately house".
In the Student Court scene, a list of Delta Tau Chi members is written on the blackboard. Writer Chris Miller's name is one of those visible on the list. Other names include "Dick Hertz" and "Duane Wayne".
The original script called for Flounder (Stephen Furst) to be admitted to the fraternity only if he told one of Larry Kroger's (Tom Hulce) secrets. Flounder blurted out, "He's got spots on his weenie!" Later, during the naming of the pledges, when Larry asks why his Delta name is Pinto, the entire fraternity drunkenly yells, "'Cause you got a spotted dong!"
John Landis sacrificed his heavy beard and much of his hair to appear in the film as a cafeteria dishwasher who catches Bluto mooching and tries, unsuccessfully, to stop him. The scene was filmed, but despite his personal sacrifices, Landis eventually also sacrificed the scene.
The original script called for a scene of competitive projectile vomiting ("booting") in the Delta House basement. Flounder was going to fail at this repeatedly. Later, after throwing up on Dean Wormer when he's told he's flunked out, Boon congratulates Flounder on his technique.
Niedermeyer's line "You're all worthless and weak, now drop and give me twenty!" was used in the Twisted Sister song "We're Not Gonna Take It" (Mark Metcalf appears in the video). In addition, the music video for Twisted Sister's "I Wanna Rock" features a high school student, clearly based on Flounder, being ridiculed by a teacher (Mark Metcalf again). At the video's conclusion, the principal (played by Stephen Furst) sprays Metcalf in the face with seltzer water.
The characters of Stork and Hardbar were created to give Doug Kenney and Chris Miller a reason to be on set, and had come from different portions of a deleted character named Mountain. Hardbar was named after a real frat brother of Miller's who masturbated excessively.
The Delta House actors were brought to the set five days before the Omega House actors to get into character, in an intentional effort to cause cliques to form. Barry Levinson would use this tactic years later with the principal cast of Diner.
The hole John Belushi makes in the wall with the guitar is the only physical damage to the house the movie-makers made during the entire shoot. Instead of repairing it, the fraternity placed a frame around the hole with an engraved brass tag around the hole commemorating it.
Professor Jennings bites an apple while lecturing about good and evil in John Milton's "Paradise Lost". This is a deliberate gag reference to Eve's eating fruit from the Tree of Knowledge, a key event in "Paradise Lost" (and referenced too perhaps by the statue pedestal motto seen in the opening titles: "Knowledge is Good"). Jennings' students miss the gag - as seems most Animal House viewers.
During interviews conducted for the 30th anniversary of this film, Karen Allen revealed some interesting trivia about her nude scene. Director John Landis wanted her to bare her bottom in the film and she was very reluctant to do so. Donald Sutherland stepped in and offered to bare his as well. Allen said "I thought he was so sweet to do that, so I sort of let go of my objections and said, 'Okay, if Donald Sutherland is going to bare his bottom, by golly, I'll bare mine too!'"
Harold Ramis wrote the part of Boon for himself to play, but John Landis felt Ramis was too old. Ramis was so disappointed he refused to accept a smaller part Landis offered him. (Ramis was 32, Peter Riegert was 29.)
To prepare for their roles, the actors playing the Deltas went to a real frat party at the University of Oregon's SAE house (except John Belushi, who was working on Saturday Night Live that night). The real fraternity members did not like the actors being there and a brawl ensued. When Belushi returned to the set and heard about the fight, he had to be physically restrained from seeking revenge.
The actors who played the Deltas harassed the actors who played the Omegas off-screen as well to keep up the feelings of animosity between their characters. Mark Metcalf changed his hotel room to the one above Bruce McGill's where the Delta actors partied every night so his anger at their noise would help him get into character.
After the first day's shooting of the homecoming parade, there was a heavy rain that night. The next day, the production crew rented a field-burning tractor that shot flames across the width of the street to dry it.
All of John Belushi's behavior in the cafeteria was improvised. He was not told to pile all the food on his tray and when he did director John Landis urged the camera operator to "stay with him." The infamous "zit scene" was also improvised. The reaction from the cast is genuine.
Originally, Harold Ramis and Doug Kenney's idea was titled "Laser Orgy Girls", a comedy about Charles Manson as a high school student. Producer Matty Simmons suggested that the setting be changed to college and the content to be toned down. Ramis also incorporated ideas from an earlier treatment he wrote titled "Freshman Year" based on his experiences in college.
The Delta actors partied together every night but John Landis kept John Belushi away from them by having him stay in a house miles away with his wife, Judith Belushi-Pisano. Belushi was a notorious partier and Landis wanted him to stay clean throughout the shoot. Belushi did host a few parties at the house but stayed clean because he saw the film as a great opportunity for him.
The final interrupting of the parade sequence was shot on the Universal back lot. This part of the lot had been used in several other films, but the section of road the parade ends up at is the same section that Robert Zemeckis used for the clock tower sequence in Back to the Future. Every angle of this street is used, but never once do you see the front of the clock tower set. The only time you do see the tower is from the back end.
The scene where John Belushi is teaching everyone the "dirty lyrics" of The Kingsmen's 1963 song "Louie Louie" is based on an actual investigation conducted by the FBI from 1963 to 1965 in which the agency spent more than 2-1/2 years trying to "decode" the song because of the supposed profanity that was "hidden" in the muffled lyrics. After spending more than two years and tens of thousands of taxpayer dollars, the agency announced that it could find no "obscene" words in the song.
The core group of Deltas (D-Day, Otter, Boone, Hoover, Flounder, Bluto and Pinto) actually traveled up to the filming site a week early, at director John Landis' request. He wanted the group to emotionally bond so that their friendship would look genuine in the film.
During their bonding week before filming, the seven Deltas partied a lot in their hotel. Bruce McGill actually stole the piano from the hotel's lobby and moved it into his room so that the group would have music.
During filming, John Belushi would often go to local nightclubs to check out the various bands. He was fascinated by a musician named Curtis Salgado. Salgado's sunglasses, harp playing and love of the blues inspired Belushi to form The Blues Brothers with fellow Saturday Night Live cast mate Dan Aykroyd.
Sean McCartin, who played the "Lucky Boy" who gets a visit from a Playmate, went on to become a pastor at a local church in Cottage Grove, Oregon. A newspaper headline about his story announced "'Lucky Boy' Still Thanking God".
In the scene where Hoover and Bluto are swearing in the new freshman, the book that Hoover is holding is actually an auto repair manual. According to the Animal House backstory, the fraternity's pledge book had actually been destroyed in a fire three years earlier.
A scene that was cut was Pinto being entertained by Boon and Hoover by telling tales of legendary Delta House frat brothers from years before. The past fraternity brothers had names like Tarantula, Bulldozer, Giraffe, and his girlfriend, Gross Kay.
After firing the crew hairdresser (who wanted extra time off), John Landis took the core Delta actors to a local barbershop and asked the barber if he could do early 1960's style haircuts. The man looked at the pictures and said it would be easy. He did all the actor's haircuts, one after another.
According to Landis, Universal Pictures president Ned Tanen protested the scene in which the Deltas take a road trip to an African-American bar by stopping a screening of the film. He ordered the scene to be removed and claimed that the scene would cause race riots in the theaters. Landis then screened the movie for Richard Pryor who wrote a note to Tanen that read: "Ned, Animal House is fucking funny and white people are crazy - Richard."
The bottle of whiskey that Bluto (John Belushi) chugs was actually colored tea. This was part of keeping Belushi away from alcohol and drugs. He was also excluded from the rest of the cast staying at Roadway Inn days prior to the shoot.
A sequel was planned that would take place during the 1969 Summer of Love and involve the Deltas reuniting for Otter's wedding. But when More American Graffiti bombed at the box-office, Universal stalled the project. The project was scrapped for good when Belushi died in 1982.
The trivia item below may give away important plot points.
Many first-run theatrical releases showed a glimpse of Clorette topless during Pinto's moral dilemma scene right after she drunkenly unhooks her bra and passes out, leaving Pinto holding the tissue with which she'd stuffed her bra. Later in the movie, right before they about to have sex on the football field, she admits she is only thirteen. By the time home video became widespread, some American obscenity laws forbade showing minors nude in sexual situations - actual or "depicted". The latter was meant for illicit composite images, but could be construed to mean acting also. The actress was 18 at the time of filming, but when her character announced her age as thirteen, a legally-problematic situation arose. Her bare chest is absent from nearly all home-use copies of the film.