The film's soundtrack became an unlikely blockbuster, even surpassing the success of the film. By early 2001, it had sold five million copies; spawned a documentary film, three follow-up albums ("O Sister" and "O Sister 2") and two concert tours; and won Country Music Awards for Album of the Year and Single of the Year (for "Man of Constant Sorrow"). It also won five Grammys including Album of the Year, and hit #1 on the Billboard album charts the week of March 15, 2002, 63 weeks after its release and over a year after the release of the film.
About 350 extras were hired for the Klan rally sequence. Many of them were members of a military formation troupe, and many were Black. Joel Coen later recalled hearing one say, 'This is the freakiest thing!'
Although Homer is given a co-writing credit on the film, Joel Coen and Ethan Coen claim never to have read "The Odyssey" and are familiar with it only through cultural osmosis and film adaptations.
Tim Blake Nelson's actual singing voice is heard during "In The Jailhouse Now." Because of this, he was the only actor in the film to receive a Grammy when the film's soundtrack won Album of the Year.
The song "Man of Constant Sorrow" was first published in 1913 by the blind Richard Burnett.
Joel Coen: [fricassee] Dan Teague tells Everett "Thanks for the fricassee," in the picnic scene under the tree. Joel Coen and Ethan Coen also included this dish in Fargo (1996) when Margie and Norm are eating in a restaurant and another cop asks her, "How's the fricassee?".