BRAVEHEART TRIVIA

Several of the major battle scenes had to be re-shot, as extras were seen wearing sunglasses and wristwatches.
Director/producer Mel Gibson was investigated by the RSPCA, who were convinced that the fake horses used were real. Only when one of his assistants provided some videotaped footage of the location shooting were they convinced otherwise.
The castle (King John's castle, Trim, Co. Meath, Ireland) where a lot of the scenes were shot, was also used to film scenes for Big Red One, (1980).

When asked by a local why the Battle of Stirling Bridge was filmed on an open plain, Gibson answered that "the bridge got in the way". "Aye," the local answered. "That's what the English found."
The extras used for the battle scenes were mostly members of the F.C.A., the Irish version of the territorial army. As they were drawn from many different army companies, and the members of these are usually drawn from the same locality, local rivalry between such companies is common. Apparently, some of the battle scenes seen in the movie are far more realistic than you might imagine, with rival companies actually using the occasion to try the beat the lard out of each other.
Wallace's real wife was named Marian, but it was changed to Murron to avoid confusion with the Robin Hood character of the same name.
James Horner's score was also used in several of the trailers for Cast Away (2000).
Mel Gibson was supposed to star in Terry Gilliam's (never made) film "A Tale of Two Cities" but turned it down to star in "Braveheart" which he then offered to Gilliam to direct, but he declined.
Real life Wallace's are extras in the movie. Mel Gibson also stayed with them during the course of the film to learn history.
The battle of Stirling took six weeks to film; roughly half a million feet of film (90+ hours) were shot for the sequence.
Screenwriter Randall Wallace had been visiting Edinburgh in 1983 to learn about his heritage when he came across a statue of William Wallace outside Edinburgh Castle; he had never heard of the 14th-century figure who shared his name, but was intrigued enough by the stories told to him about "Scotland's greatest hero" to research the story as much as possible.
Randall Wallace had very little historical evidence to work with in regard to William Wallace's life; he has noted that even Churchill's definitive work "A History of the English Speaking Peoples" observed in only a single line that virtually no factual material survives about the Scottish leader. Because of this, Randall Wallace relied heavily on a 15th-century romantic poem by the Scottish writer Henry the Minstrel ("Blind Harry") in constructing his story.
Writer Randall Wallace initially planned to start the story with William Wallace as an adult, and added the prologue of his childhood only as an afterthought. As the sequence was first written, Murran gave William a rose (rather than a thistle) at his father's burial; however, someone who read the script helpfully pointed out that the rose, being a traditional symbol of England, would be (to say the least) somewhat inappropriate as a prominent feature in the story.
Glen Nevis, the Scottish valley which served as the location for Wallace's childhood village, also enjoys the heaviest rainfall in Europe. During the six weeks spent filming in the area, only three days of sunshine occurred - in which the wedding scene was finished. The filmmakers resigned themselves to the fact that constant rain was inevitable, and opted to film scenes regardless of weather conditions.
Thin layers of latex were used to attach set elements to the ruins of Trim Castle in Ireland, to give it an appearance more befitting its medieval origins while allowing the stone to be unharmed when the additions were removed.
The mechanical horses designed for the battle sequences weighed 200 pounds and were fueled by nitrogen cylinders propelling them at 30 mph on 20-foot tracks.
Single frames of film were removed at strategic points in the battles in order to produce a jarring, startling effect.
The British royal family, from the 15th century forward, has been descended from both King Edward I and Robert the Bruce, as their respective descendents Joan Beaufort and King James I of Scotland married in the early 1400s - barely a century after the battle of Bannockburn in 1314.
The film correctly depicts the father of Robert the Bruce suffering from leprosy in his later years; Robert the Bruce himself would be overcome by the disease in the late 1320s.
Prince Edward (later King Edward II) was indeed the first English prince to carry the title Prince of Wales, although he did not marry Princess Isabella until 1308, after both Wallace (1305) and Edward I (1307) had died.
Mel Gibson is 5'11", while the real William Wallace was 6'6", and his sword was 5'7". Hence, the sword Gibson wielded in the movie was considerably shorter than Wallace's original.
The only way Gibson could get the film made was if he agreed with Paramount studios that he would star in the film as well.
Gibson, a notorious jokester, directed some scenes in an Elmer Fudd voice and even yelled "CUT!" during Murron's funeral scene by putting his arm around the actress playing her mother and hollering, "Will you put a sock in it!" This caused the actress to go from crying in character to break character and laugh... Gibson also intentionally started a false rumour that Sophie Marceau was the daughter of noted French pantomimist Marcel Marceau.
Though Princess Isabelle did not marry Prince Edward until after Wallace's death, she and her husband did have an extremely unhappy marriage that eventually led to her arranging for the murder of her husband (executed by inserting a red hot poker into his anus).