Continuity mistake: If you look carefully at the monster (Frankenstein) you will see that his face is different in the ending scenes. The reason is, during the movie you see the monster take the woman doctor and throw her out the laboratory window. You then see the monster kind of stumble, which he really did and broke his ankle. So in the final scenes they replaced Lon Chaney Jr. as wolfman with a stuntman, and Lon Chaney Jr. finished the movie as the monster.
Factual error: After the first encounter with the Apaches, the covered wagon is headed to the Fort at full speed. The camera pans to the Apaches on the ridge and you can see a truck driving at the bottom right corner. (00:32:00)
Revealing mistake: When the American pilots flying P-47 Thunderbolts are attacked by German fighters, the German planes are really American P-51 Mustangs painted with German markings.
Factual error: When the riders are watching the wagon train, in the background you can see a communication tower with conical speakers.
Continuity mistake: During the dinner party, Philip crushes a glass in his hand, and we see that his hand is cut and bloody before he wraps a piece of cloth around it. Later on, when Mrs. Atwater reads his palms, not only is there no bandage, but there is also no blood or sign of a cut on his hand.
Continuity mistake: Near the end of the movie, Lucinda is severely injured in her leg, and has to hobble to walk. In the last scene (a short time later) as she approaches her home, she is walking with no problem, and has her arm in a sling.
Plot hole: When Ralls runs the Witch onto the reef, he is at the helm. As she strikes bow on, the wheel spins madly for no reason, as the tiller ropes would not have been affected by the collision.
Continuity mistake: When Donald comes out of his tent at the beginning, he is holding a coffee pot and a cup and puts them down on the picnic blanket. When we see the blanket after Donald has put on his napkin, the coffee pot and cup have disappeared.