In Guinness World Records 2001, this film was said to have the most profanity used in an animated film. The book cited a total of 399 swear words, including 146 uses of the word "fuck", along with 199 offensive gestures and 221 acts of violence.
In the film This Film Is Not Yet Rated (2006), Matt Stone claims that the original idea for Cartman's mom's Internet video was of her having sex with a horse (but the act wouldn't be seen on screen). The MPAA would not allow this because of bestiality, despite the fact the at one point in the movie, a picture of a man having sex with a horse is seen (when Dr. Vosknocker is trying to get Cartman attempt to swear and one of his flash cards is "horse fucker"). So Stone and Trey Parker decided to make the Internet video of a German guy defecating on Cartman's mom, and the MPAA approved it.
Paramount originally asked Trey Parker and Matt Stone if they could make a PG-13 rated film. They said no and would not agree to make a movie until the studio agreed that the final product would be rated R.
Parker and Stone did not need to get Brian Boitano's permission to use his name and likeness for the song "What Would Brian Boitano Do?". A few years later, Boitano DID need to get (and received) Parker and Stone's permission to use the phrase on T-shirts that he sold for charity.
It's a widely reported myth that the original title of the film was "South Park: All Hell Breaks Loose" and the MPAA forced Trey Parker and Matt Stone to change the title, stating that all movie titles must be G-rated (despite the fact that there are many movies with the word "hell" in them - Hellraiser (1987), Hellfighters (1968), From Hell (2001), etc.). The story comes directly from Parker and Stone who claim that they submitted the film with the original title and were forced to change it. Richard Taylor, a spokesman for the MPAA, denies that any film was ever submitted with that title and that the MPAA did not reject the use of the word "hell" in the title.
During the scene where South Park residents are burning everything Canadian, the soldiers in the background are named 'Wright' 'Floyd' and 'Mason', referencing drummer Nick Mason and keyboardist Richard Wright, both of the band Pink Floyd.
The song "What Would Brian Boitano Do?" is a reference to the original Christmas Card "The Spirit of Christmas" which was the inspiration for the South Park (1997) series. In the short, Stan asks Cartman, "What would Brian Boitano do?" when Jesus is fighting Santa.
When the children are in rehab, a poster in the back of Mr. Mackey's room reads: "Get High!!! On Pottery", a quote from a high school teacher of Matt Stone's. Original quote: "Son, you need to know not to use pot as a natural high. Instead of getting high with pot, get high with pottery."
When the boys are watching the video of Cartman's mom on the Internet, the button that would normally say "stop" on the Netscape toolbar has been replaced with an obscene drawing and labeled "Sphincter".
Parker, Stone, and fans in general often joke that a majority of the people who saw this film where under 17, and got in by buying tickets to the PG-13 rated Will Smith failure Wild Wild West, the urban legend became so popular in 1999 that the show would spoof the controversy in an episode of the show.
The ending of the song "Uncle Fucka" (sung by Terrance and Philip in the movie-within-a-movie) makes reference to the famous title song from Oklahoma! (1955), in which the title of the song is spelled out letter by letter.
In the short segment of soldiers marching to the U.S.O. show while singing a cadence song, Jesus Christ appears in the ranks for a moment before the scene transition to Kyle hiding Ike away in the attic.
The original trailer which took jabs at Walt Disney and animation in general was so hated by Parker and Stone that they called it "everything we didn't want the film to be" and Trey Parker was so upset he dismantled the videotape of the trailer and threw in the trunk of his car, then told the Production crew in anger to "do it again"
According to a pie chart, the entire Canadian economy is based on Terrance and Philip, the snow ball machine, the tourist industry, the log industry, the porn industry, the "Dion Fish" industry, and filming The X-Files (1993).
When Sheila Broflofski holds up the newspaper article about Terrance and Phillip being on the Conan O'Brien show, there are other headlines, including "It's Raining Frogs!", "Christians Agree: Guns Are Nifty", and "Poop Ruled Edible".
The trivia item below may give away important plot points.
Body count before Kenny's wish: 312; after his wish: 7. Since Kenny wishes for everything to go back to the way things were before the war, only those who died prior to the war would remain dead: Kenny himself, Saddam, Conan O'Brien, and the four Baldwin brothers (Alec, Daniel, William, and Stephen).