Continuity mistake: After being knighted, William says that he will invade England. In the close-up shots of Robert in the group reacting to him saying this, you can see the man whose bride was taken away by the English lord earlier in the film behind him. But, in the wide shots, he's not there. It's just some random man behind him.
Continuity mistake: In a major fight scene two soldiers on opposite sides are jumping and spinning and tapping each other on the head with their swords.
Continuity mistake: In one of the major battles, Wallace is charging down a hill with a large sword in his hand. During the charging it changes to being a small pick axe type tool. Then around the middle of the charge there is a quick shot change and almost from the same angle the pick axe has disappeared. It then changes back to a large sword, a quick change back to the pick axe, then back to the large sword. (01:28:20)
Continuity mistake: At the end when Wallace is being led to be executed, he is pelted with food. Much of it sticks to his face and hair. A few moments later when they are standing him up he is completely clean. (02:37:50)
Visible crew/equipment: During the "full attack" at the start of the Battle of Stirling Bridge, Wallace repeatedly shouts, "Hold," and in the wideshot right before Wallace finally shouts, "Now!" as the horses gallop towards the right side of the screen, we can see a white car at the left side of the screen. Viewed widescreen version. (01:27:15)
Revealing mistake: At the end, Wallace's friend is charging in slow motion, and if you look closely you will see his battle axe flopping around like it's made of rubber. (02:49:50)
Other mistake: When Robert the Bruce returns to the battlefield at Falkirk, there are 2 children supposedly crying over a loved one. If you look at the blonde girl she is actually laughing. (02:12:00)
Revealing mistake: After Wallace kills the Scottish noble in bed, he jumps out of the castle window into a river on a horse. As he is falling, you can see that the horse is a model and when they fall into the water one can see the fake horse bobbing around. (02:15:45)
Continuity mistake: In the first large battle with England at Falkirk the same scenes are used when the English fire the arrows. The first time the arrows are fired, a blonde young man is hit in the foot, they then moon the English so they fire again and the same man is seen getting hit in the same foot. A man in the same battle is shot in the hip - when he grabs the wound you can see the shape of the cushioned bulb that the arrow is attached to. If you watch during all the battle scenes you can detect men who are supposed to be on opposite sides standing and talking, also you can see the choreographed moves being played out in almost slow motion - their swords aren't even striking.
Continuity mistake: At Stirling an English archer is hit by the nobles on horseback causing his helmet to fall off. He's then hit again and somehow his helmet falls off again. Then when he lands he is still wearing his helmet despite it having fallen off (twice).
Continuity mistake: When the English spy tries to kill Wallace, and you realize the crazy Irishman is a friend, you see the spy drop his sword, as soon as he is hit by the Irishman's weapon, but as soon as he hits the ground dead, the sword is back in his hand. (01:08:30)
Continuity mistake: When Wallace tries to escape from the English with his wife, not knowing that she has been captured and executed, he is seen running through the woods screaming her name... As he's running he has a sword in his right hand. During the course of three or four camera shots, the sword he is holding magically disappears and reappears as different cameras shoot him. Then it reappears and he digs it into the ground as he takes off the English soldier's uniform that he stole. (00:42:35)
Factual error: The Battle of Stirling (Bridge) is shown inaccurately in the film: the English and Scots line up on a battlefield and proceed to set about each other, with the Scots winning, with no bridge in sight. In the actual battle the English were crossing a bridge over the River Forth. The bridge was narrow, so they had to file down into small ranks. Wallace and the Scots waited at the top of a hill until half the army had crossed, then, before the English had time to regroup and form battle lines, the Scots charged down the hill and massacred the unprepared English.