Mel Gibson initially turned down the role of William Wallace, feeling that he was too old for the part (Gibson was 38 at the time, while the real Wallace died at 35) , but Paramount Pictures would finance the film only if Gibson starred in it, so he agreed.
In an October 2009 interview with "The Daily Mail," Mel Gibson admitted that the film was heavily fictitious, but claimed the changes had been made for dramatic purposes. He also admitted he had always felt he was at least a decade too old to play Wallace.
One of the film's weary extras reportedly mistook one of Mel Gibson's children on the set for an errand boy, and asked him to bring a cup of tea. Gibson was within earshot, and nodded and whispered to his son, "Go get it."
Up to 1,600 extras were used for the battle scenes. Most were members of the F.C.A., the reserve Irish Army. Different companies usually come from the same area, and rivalries are common. Apparently some of the battle scenes are far more realistic than intended, with rival companies trying to beat the lard out of each other.
While most of Wallace's home scenes were filmed in Glen Nevis in the Scottish Highlands, much of the latter scenes were filmed in Ireland, including the major field battle scenes.