William H. Macy begged the directors for the role of Jerry Lundegaard. He did two readings for the part, and became convinced he was the best man for the role. When the Coens didn't get back to him, he flew to New York (where they were starting production) and said, "I'm very, very worried that you are going to screw up this movie by giving this role to somebody else. It's my role, and I'll shoot your dogs if you don't give it to me." He was joking, of course.
Joel Coen had Frances McDormand and John Carroll Lynch conceive a back-story for their characters to get the feel of them. They decided that Norm and Marge met while working on the police force, and when they were married, they had to choose which one had to quit. Since Marge was a better officer, Norm quit and took up painting.
William H. Macy stated in an interview that, despite evidence to the contrary, he did hardly any ad-libbing at all. Most of his character's stuttering mannerisms were written in the script exactly the way he does them in the film.
Frances McDormand wore a "pregnancy pillow" filled with birdseed to simulate her pregnant belly. She says that she didn't deliberately try to move in a "pregnant" way, it simply came as a natural response to keeping the extra weight balanced.
The duck paintings briefly shown in the Gunderson home were painted by "those Hautmanns," who are close friends of the Coen brothers. These three brothers frequently win federal and state wildlife stamp competitions.
When Jerry is first seen talking to the man from GMAC on his office phone, the scene was set up with the horizontal blinds in his office windows open to give the appearance that Jerry is in a jail cell due to the scam he is obviously putting out to GMAC over the fake sales invoices which constitutes as finance fraud and embezzlement.
In the kidnappers' cabin, Bruce Campbell can be seen on the fuzzy TV screen. Bruce Campbell was in the Coen Brothers' The Hudsucker Proxy (1994) and has been in various films by Coen buddy Sam Raimi. The footage was not shot for this film, but was actually old footage of a regional soap opera in which Campbell appeared.
Approaching Brainerd from the south, you see a statue of Paul Bunyan with a sign reading "Welcome to Brainerd." In reality, Brainerd has no such statue. Paul Bunyan Amusement Park, located just outside Brainerd, had a huge statue of Bunyan and Babe the Blue Ox. The park is now at 'This Old Farm,' between Brainerd and Garrison.
Early in the movie Wade is watching a University of Minnesota hockey game. At one point an announcer can be heard saying "goal by Ranheim" and the TV shows the Gophers playing Wisconsin. The goal scorer would be Paul Ranheim, who scored 88 goals for Wisconsin from 1984 to 1988 and later played in the National Hockey League with Calgary, Hartford/Carolina, Philadelphia, and Phoenix.
The morning talk show hosts on the TV right before Mrs. Lundegaard is kidnapped were actual Minnesota morning talk show hosts for many years during the 80s and early 90s. They hosted a show called "Good Company".
During the interview process at the Blue Ox where Frances McDormand interviews Melissa Peterman "Hooker #2", she mentioned she's from Le Sueur (MN) but amplifies her answer to include the high school she attended in White Bear Lake (MN). White Bear Lake Area High School (complete with bear mascot - "Go Bears"), formerly White Bear Lake Mariner High, is approximately 75 miles northeast of Le Sueur but significantly closer to Chaska (MN); the birthplace of Larissa Kokernot "Hooker #1" and the probable rationale behind the erroneous association. Although, Hooker #2 never says that White Bear Lake is near Le Sueur.
The reference to "Midwest Federal... talk to ol' Bill Diehl" is a nod to film critic Bill Diehl, who wrote for the St. Paul Pioneer Press-Dispatch and interviewed the Coen Brothers shortly after the release of Blood Simple. (1984) Midwest Federal Savings was part of the savings and loan crisis, and folded--largely as the result of bad real estate investments--in 1989, two years after the story takes place. The Midwest Federal Building, the S&L's Minneapolis headquarters, was used for exterior shots of the building in which WJM was located on Mary Tyler Moore (1970).
Carl says he's in town for "just a little of the ol' in-and-out," a reference to A Clockwork Orange (1971). When Carl and Gaear are driving outside Minneapolis, the song 'These Boots are Made for Walkin' can be heard on the radio, a reference to Full Metal Jacket (1987), which features the same song.
The trivia items below may give away important plot points.
The film is not actually "Based on a true story". Joel Coen & Ethan Coen later admitted that they added that disclaimer so the viewer would be more willing to suspend disbelief in the story. (An urban legend even says that people have gone to search Minnesota for the briefcase of money, and come to a bad end.) While the specific crimes in the movie didn't happen, the plot has elements of two well-known Minnesota crimes. In 1962, a St. Paul attorney named Eugene Thompson hired someone to kill his wife, Carol. Unbeknownst to Thompson, his man hired someone else to do the job. The second man fatally wounded Mrs. Thomspon in her house, but she managed to escape him. She went to a neighbor's house for help while her assailant fled the scene. The sloppiness and brutality of the crime attracted great attention. The murderers were quickly caught and gave up Thompson, who denied knowing anything about the crime for many years afterward. In 1972, Virginia Piper, the wife of a wealthy Orono banker, was kidnapped. A million-dollar ransom was paid, one of the largest in U.S. history. Mrs. Piper was found tied to a tree in a state park. Two men were convicted of the crime, but were acquitted after a re-trial. One of them later went on a shooting spree after his wife left him, killing her, their 5-year-old son, her son from a previous marriage, her new boyfriend, and one of his sons. Only $4,000 of the money was ever recovered.
Despite hints to the contrary at the time of the film's release and in the closing credits, Prince does not play the Victim in the Field; this is J. Todd Anderson, who was actually a storyboard artist on the film. This was yet another Coen Brothers in-joke, since Prince was a famous native of Minneapolis, Minnesota. To further muddle matters, this moment in the film was memorialized in a "Snow-Globe" promotion included with a special edition version of the DVD, subtly hinting that the dead victim in the snow was a famous cameo.