Factual error: When the posse arrives at the mission, a horizontal jet stream can be seen during this scene. (01:00:00)
Revealing mistake: Although the film is set during the aftermath of the Mexican War (1848-50), the mountain vistas display some lovely radio towers and fire ranger stations.
Visible crew/equipment: When Robert and Arvid are in the desert and Robert falls into the pit, you can see the shadow of director Jan Troell holding the camera.
Other mistake: In the shot where the men are playing a game of baseball, if you look carefully in the background you will see that cars are driving down the highway. Considering that this movie was supposed to take place in the 1800's...