Continuity mistake: When the butler takes the mother and kittens to be abandoned in the countryside he is on a motorcycle and sidecar combination. During the trip the sidecar changes from one side of the bike to the other and back again. Also, when the sidecar separates from the motorcycle when the dogs are chasing Edgar, the wheel on the sidecar switches sides regularly as well.
Factual error: As the colonel and his companions ride out of Blackthorne, Texas, they pass Saguaro cacti, which, oddly enough, only grow in the Sonora Desert, a far distance from Texas.
Factual error: In the scene where the king attempts to seize the five members from Parliament, Cromwell makes a dramatic refusal to leave and proposes various "Laws" to prevent his arrest. Cromwell was not one of the five members whom the King tried to arrest and no law can come into force until it had been signed by the reigning Monarch anyway.
Revealing mistake: Near the end of the film, there is a football game played between the rival MASH units. Although the game is supposed to be taking place in a remote location of Korea in 1951, late model 1960's automobiles can be seen driving on a nearby highway as the game progresses. This gave away the fact that the football scenes were shot at a university in Southern California.
Other mistake: About 3/4 of the way through the film a boat arrives at the left quay of the Seine. Looking west down the river with Notre Dame on the right of the scene you can see a tour bus cross the bridge.
Continuity mistake: About 3/4 through the film, which is supposedly set in the 1900s, there's an exterior shot of Jenny Agutter (as Roberta) talking to William Mervyn (as "the old gentleman"). Over Mervyn's shoulder can be seen a white delivery van driving rather fast along a road on the other side of the valley from where the filming took place (this is very obvious in the wide-screen version but less noticeable in the pan-and-scan TV version).
Continuity mistake: When Erica eats the cat the telephone is on its side, then the right way up.
Revealing mistake: The cannons shown are firing blank charges, which produce no recoil. Recoil has been simulated by towing the guns backwards when they fire. The problem is, there is always a distinct delay between the discharge and the "recoil." The cannon also seem to largely fire explosive shells. At no point do we actually see a cannon ball rolling or bouncing along the ground or into any group of soldiers.
Continuity mistake: When the man puts jelly down his wife's dress during the food fight, Jenny Grubb's arm is not on the table. In the next scene, her arm is resting on the table, but in the scene after that, her arm is back in its normal position.
Continuity mistake: Burt Lancaster is sitting in his car at the end, and he asks the tower if he can listen to the radio traffic for the incoming plane that's landing. The tower replies "Sure, it's on frequency 117.1". Burt then tunes the dial on his receiver to 171, not 117. 170 is blatantly written under the dial in bold type.
Revealing mistake: When the mayor's wife attempts suicide by stuffing herself with pills, she is lying behind a sofa, only her arm and the pill bottle being visible as she pours the contents into her mouth. In the next shot (a close-up), however, the crown of her head is visible, and it is evident that she pours the pills over the top of her head.
Revealing mistake: During the Little Bighorn massacre one of Custer's lieutenants turns to address Custer and is struck in the back with an arrow, and the thick pad or board is visible under the actor's shirt.
Continuity mistake: In one scene when Hudson and Andrews enter the vestibule of her house, Rock can clearly be seen to have "mutton chop" sideburns. However, once inside the house, they're gone. When he goes back outside, they're back.