Continuity mistake: In the scene after Gabriel dies, the camera pans down from the top and you see the U.S. flag with all fifty stars, but when Benjamin leaves the tent it has only thirteen on it.
Continuity mistake: Gabriel writes in his letter that his friend was killed at Elizabethtown, but you can see that the letter actually states he was killed at Monmouth.
Visible crew/equipment: In the final battle scene where Benjamin is fighting Tavington one-on-one, the camera angle widens and shows the whole battle scene. In the bottom right corner, you can see another camera filming the action.
Factual error: In one scene Lord Cornwallis' adjudant announces to Lord Cornwallis that a messenger (Benjamin Martin) has arrived. After initially dismissing the message, Lord C. pays attention on the mention of two "Great Danes" in Martin's company. The Great Dane as we know it today had many names over the centuries, but the Danish connection only became common use in the 19th century (Comte de Buffon - l'Histoire Naturelle - 1811). Until then the British would have called them Mastiffs (English or German), English Dogges, or perhaps even Boarhounds. Actually - the English Kennel Club of Britain didn't officially recognize the term/breed "Great Dane" until 1884.
Factual error: When Benjamin is handing a store clerk some money, you can see that he is giving him a $5 bill with Abraham Lincoln on it. This happened more than 80 years before he was president.
Revealing mistake: When Benjamin and Harry are talking on the steps of the legislature of Charlestown after deciding to go on war with the British, you can see a man behind them with something in his ear, a hearing aid or earpiece.
Continuity mistake: In the shot where Tavington is loading his pistol (before he shoots the Rev.), he throws his ram rod, but when Benjamin's son is going to shoot him he has it back (he did not have an extra).
Revealing mistake: In the shot where Benjamin is riding his horse to the top of the hill, the camera pans from left to right and in the distance is the British army. But if you look to the left the trees are way too huge (a bad scale). If Benjamin had ten militamen cut one down, it would have wiped out 1/4 of the British army shown.
Continuity mistake: The beginning starts in 1776. The film ends in the year 1781 with the battle of Cowpens, a five year period. The children in the film do not age in that five years, except the youngest and that is after what I judged a six month period.
Continuity mistake: When John Billings, a member of the militia, finds his wife and child murdered and his house burned by Tavington's Green Dragoons, he promptly shoots himself in the head. But later in the movie, at the ending battle of Cowpens, you can see him standing in the ranks, getting shot if you look closely.
Revealing mistake: When Tavington has sliced Benjamin across the back in the final battle, Benjamin falls to his knees and the bayonet on the end of the gun he's holding, which is supposed to be metal, jiggles like rubber when the gun hits the ground.
Continuity mistake: When Benjamin comes down the steps out of the meeting, he walks towards his oldest son signing up. He approaches his son and his son is facing away, but they cut back to Benjamin and his son is facing him. They cut back to the son and he turns around and then back to Benjamin and it's the same shot again. His son was turned around before he turned around.
Revealing mistake: In the shot where General Cornwallis says, "Unless I'm dreaming..." The shot is through his telescope. Notice that he's on a tall hill but the shot is almost level to the ground and it's moving down.
Continuity mistake: When Benjamin rides over the hill holding the fluttering flag, the flag is in his left hand. In the next shot, the flag is in his right hand, and the flagpole base is in a scabbard attached to the saddle.
Factual error: During the American Revolution, men saluted by taking off their hat and lowering to their side, then putting it on again. In the movie, Gabriel (Heath Ledger) salutes by placing his hand on his head....the way we are used to now.
Factual error: All soldiers in the Continental Army are wearing the same uniforms. Officers and enlisted men wore significantly different uniforms.
Continuity mistake: In one battle scene, a soldier's head is knocked off by a cannonball but the same soldier appears in a later battle scene, complete with head.
Continuity mistake: In the final battle scene, when you see the British in the distance from the Americans' point-of-view. There is a fence in the middle of the field, but when the two armies engage each other the fence disappears.