Continuity mistake: When Leonidas, and presumably all the other Spartans, use their spears to clear their shields of arrows after the arrow shower from Persian archers, the tips of the arrows are still visibly left on all their shields. In the next shot, when the Spartans regroup for the Persian cavalry charge, the arrow tips are gone. (Granted, this is a highly stylized movie based on a comic book, but that does not change the fact that this is a continuity error.)
Factual error: When the Marines strip off and run into the sea in the final scene, Doc takes off a pair of white socks that would be more appropriate for a final at Wimbledon. Not only are they white rather than khaki, they are virtually spotlessly clean which would be impossible after a week of fighting on the black sands of Iwo Jima.
Visible crew/equipment: When Dieter steals the rifles from the hut and approaches the other prisoners before their attack on the kitchen, a crew member (wearing a cap) can be seen moving from the right of the screen to the left with a camera or some other equipment. (01:19:35)
Continuity mistake: When Jack shoots the cop Urick, the slug perforates his suit coat, both front and back, as well as his right lung. However, when he rendezvous with the Russians atop the parking garage, his suit coat is pristine. Had he changed into another identical coat, would he have not changed his bloody shirt and tie at the same time?
Factual error: During the movie the Germans are more then once using halftracks of the type sonderkraftfahrzeug 251, which originally were only allowed to be used by panzerdivisionen (armored divisions), and at the moment the movie is supposed to take place, there were no panzerdivisionen in Holland.
Factual error: Sharpe follows a wagonload of powder kegs into the Western Gatehouse, then down a corridor lit with torches, to the end of the corridor where Indians were tying together quickmatch, once again by torchlight. With the propensity for powder kegs to leak, even an Indian subadar would use closed lanterns.