Other mistake: In the final scene, just after the death of Magua, you can hear a small dog (perhaps one owned by a cast, or crew member, but unlikely to be a breed out in the wilderness away from human shelter) barking. (01:46:20)
Suggested correction: Laughable. There is no audible barking of a dog.
Revealing mistake: Near the very end of the movie, when Magua has taken Uncas' love interest (Madeleine Stowe's character's sister) and he is taking a path through the mountain, Daniel Day-Lewis runs up a path and brushes against what seems to be a rock. But, the grey coloured "rock" seems to be a prop and moves like a piece of cloth.
Visible crew/equipment: When the people are all marched out of the fort, in the lower right hand corner there is a guy wearing a blue baseball hat.
Revealing mistake: After they leave the fort, in the forest glade when the Huron start hollering, the air above the soldiers is very clear. But in the next shot just when the guns start to fire, there is a smoky haze hanging over the forest. Apparently the first attempt to film this scene didn't make it to film and some of the residual smoke was still there when they filmed it the second time.
Factual error: Toward the beginning of the film, when Natty Bumppo first arrives at this friends' cabin, he mentions that he was coming from Schuylerville. This is an anachronism as Schuylerville, NY, was named after the victorious General Schuyler at the Battle of Saratoga in 1779, which would not take place until 20 years after the events of the film. The town would not assume the name for another 50 years after that.
Visible crew/equipment: At the beginning of the scene, when the evicted fort dwellers are making their way through the forest, as the column moves away from the camera, a crew member with a red baseball cap and a megaphone comes into shot.
Visible crew/equipment: As they are leaving the fort, during the point of view shot of Cora, on the left hand side of the screen, a black gas canister can be seen.
Continuity mistake: When Daniel Day Lewis, his brother and father are going after the Munro girls and the officer, in one scene where the dark haired Munro girl falls against a bush and breaks the branches. If you look closely at the scene before, the branches are already broken.
Revealing mistake: Uncas dies and falls off the cliffside. Immediately after this happens, Hawkeye comes into view through a passage in the rocks. If you look at the rock to Hawkeye's left, when he touches it with his hand, it flexes.
Continuity mistake: During the walk to Fort William Henry, at one point, Uncas, the true Mohican son, turns to look at Alice who is struggling and his earring is in his right ear. During the rest of the movie, the earring is in the left ear.
Factual error: In real life, Colonel Monro and the Marquis de la Montcalm never met face to face to discuss surrendering Fort William Henry. Monro was also not scalped but died of illness months after he surrendered.
Deliberate mistake: Rhododendrons, visible in the opening scene and mentioned specifically in the shooting script, do not grow in the Adirondacks.
Factual error: When Hawkeye shoots the elk in the opening his rifle emits a muzzleblast, but the priming powder in the pan does not leave its characteristic smoke. When a flintlock is fired two distinct clouds of powder smoke should be seen.
Audio problem: Shortly before jumping through the waterfall, Hawkeye says to Cora, "If we go there's a chance there won't be a fight." However, if you watch Hawkeye's mouth, the audio doesn't match his lip movements.
Audio problem: When Magua complains to the Marquis about not getting his revenge after Colonel Munro's surrender, the Marquis' lips don't match the audio whenever he says Magua's name.
Continuity mistake: When Chicanghook is swinging his club at Magua, he's aiming for the left arm, but in the next shot he hits the right arm.
Revealing mistake: When Uncas is being murdered and thrown down, Daniel Day Lewis comes running from between the rocks. He then hits the rocks on the viewer's left side. You can see them moving since they are made of linen.
Other mistake: When Hawkeye, Uncas, and Chingachgook jumped through the waterfall, their gunpowder was, according to Hawkeye, soaking wet. When escaping from the Huron camp, Hawkeye suddenly has dry powder to put the burning British officer out of his misery. Nowhere do we see our three heroes get dry powder. And no, sodden gunpowder can't be dried out and reused.
Visible crew/equipment: Right before Munro is attacked by Magua and killed, there is a shot of a soldier falling right toward the camera. The shadow of the camera becomes very obvious on him.
Continuity mistake: When Uncas single-handedly attacks Magua's party on the mountain, he shoots an opponent who is filmed falling off the side of the mountain. When the camera cuts back to the fight, you can see him fall down again on the far left (while Uncas is attacking the next one in line).