Revealing mistake: The U.S. Army killed the wolf friend of Dunbar, and in the following scene, the camera shows the wolf body while the Army moves away. If you stop the scene, you can see that the "wild" wolf has a strap around his neck.
Revealing mistake: During the buffalo hunt, where the buffalo turns to charge the fallen Indian, the buffalo has a nose ring used for leading domestic animals.
Revealing mistake: In the scene where Dunbar comes to the Indian camp with the wounded woman he found, she is supposedly knocked out. However, when the Indian warrior grabs her wrist and pulls her to the tribe, she is also hanging strongly, with her hand around his wrist.