Director Brian Helgeland once said in an interview that he used modern music in the movie to show modern audiences what people then felt about their music. When true Renaissance music is used in modern movies, it fails to convey the emotional response that people back then had to such music.
When Chaucer first introduces "Sir Ulrich" in his speech, the crowd doesn't react at first because the Czech extras didn't understand the speech. Mark Addy's loud prompt was what tipped them off to start cheering. The awkward moment was left in because it made the scene more funny.
The initial scene of the two knights jousting in the first scene of the movie is actually footage of Heath Ledger's stunt double in an accident. While filming a later scene, the stunt double's opponent's lance moved off target and hit him in the head. The double fell to the ground unconscious. The entire scene was used for the introduction.
Plenty of effort was expended creating lances that would splinter convincingly without taking out the stunt riders as well. The body of each lance was scored so it would break easily, and the tips were made of balsa wood. Each was also hollowed out, and the hole filled with balsa chips and uncooked linguine to make convincing splinters.
When Chaucer first introduced Sir Ulrich at the joust, he makes a point of including the lower classes, saying "And everyone else here not sitting on a cushion". This is a reference to The Beatles' Royal Commend performance in 1963 when John Lennon introduced the last song by saying "For the people in the cheaper seats clap your hands. And the rest of you, if you'd just rattle your jewelry".
During the first award ceremony with William and Adhemar, Chaucer kisses Count Adhemar's herald twice. This was the response to a request from director Brian Helgeland to "surprise him", though he never specified how.
Heath Ledger knocked out one of director Brian Helgeland's front teeth with a broomstick when the two were demonstrating a jousting move. It was several months before Helgeland's mouth had healed enough to repair the damage. He says it was the only jousting injury during filming.
In earlier scenes in the film, Jocelyn refers to Ulrich/William as "a hunter". At the end, when they are embracing and the scene dissolves to a night-time sky scene and then pans away, the camera clearly shows the constellation known as Orion - the Hunter.
The terrific crunching sound heard whenever a lance shatters in the film is largely made up of the sound of a howitzer being fired. In order to produce the long crunching impact, the sound of the howitzer was slowed down by half.
The part where Jocelyn tells William to prove his love by doing his worst in the tournament appears to be taken directly from Guinevere and Lancelot's romance in Chrétien de Troyes' 12th-century poem "Lancelot, the Knight of the Cart".
The expression "it's sixes and sevens" is used in its gambling context by Simon the Summoner to get Geoffrey Chaucer to gamble. The phrase is derived from the game of dice, and originally appeared in print in Chaucer's Troilus and Criseyde, 1374. It means "to carelessly risk one's entire fortune".
The video version of the film, released prior to the terrorist attacks on the World Trade Center on 11 September 2001, was recalled because it contained a Spider-Man (2002) preview that included a shot of the World Trade Center.
Several of the named knights were, in fact, real, though many of them are from different time periods. Ulrich von Lichtenstein was a knight and author who was said to have invented the concept of chivalry and courtly love. Piers Courtenay was a descendant of Edward I, born in the 15th Century. Sir Thomas Colville, Edward III's disguise, was a knight from the 13th Century. Lord Roger Mortimer was the lover of King Edward II's wife - Isabella of France - and was hanged, drawn, and quartered by the Black Prince's father, King Edward III. The real-life Ulrich von Liechtenstein was a real knight, and regular jouster. He boasted that he would give a golden ring to any knight who could break a lance on his armour, giving away 271 in total, but remaining undefeated.
Newsweek revealed in June 2001 that print ads for at least four movies released by Columbia Pictures, including this film and The Animal (2001), contained glowing comments from a film reviewer who did not exist. The fake critic, "David Manning," was created by a Columbia employee who worked in the advertising department. "Manning" was misrepresented as a reviewer for The Ridgefield Press, a real, small Connecticut weekly paper.
The film is intentionally anachronistic and not meant to be historically accurate, but although the real-life Edward is often referred to as the "Black Prince", there is no record of this name being used during his lifetime, nor for more than 150 years after his death. He was instead known as Edward of Woodstock (after his place of birth), or by one of his titles.
In the movie, Chaucer uses the phrase "gilding the lily". The real Chaucer died in the year 1400. However, the first documented reference of the phrase is from the USA in 1895. It probably derives from a Shakespeare's play "King John" written in the mid 1590s and first published in 1623 in the First Folio where Shakespear writes "To gild refined gold, to paint the lily".
Chaucer refers to Sir Ulrich as the "seeker of Serenity", Alan Tudyk who plays Wat in this movie is most known for playing Hoban Washburne the pilot of Serenity in Joss Whedon's Firefly (2002-2003) and its film Serenity (2005)
Shortly after our heroes meet Jeffrey Chaucer on the way to Rouen for a tournament, Wat explains to Chaucer that if he betrays them he will fong him until "... your insides are out and your outsides are in" which can be found in the Beatles song "Everybody's got something to hide except for me and my monkey" from the White Album.
The trivia item below may give away important plot points.
After Adamar sees Will in Cheapside, the camera pans over London. In the top right hand corner of the screen, you can see The Millenium Wheel in the distance, although the silhouette is thicker than in reality; as if it is made of wood.