Patzer

Near the end during the big Indian attack, the soldiers blow up a wagon full of powder to deter the Indians. A few seconds after the 1st explosion, a slightly different camera angle shows a second explosion which is identical to the 1st. Although the wagon is fully engulfed in flames after these explosions, a minute later as the Indians retreat, the wagon is not on fire but on a subsequent shot, a small flame is now evident.

In the fight scene around the campfire between Fred MacMurray and another member of the wagon train, Fred's hat is definitely lost early in the scuffle. After landing a right jab and knocking his opponent down the camera cuts to the man on the ground and Fred (via his stunt double) leaps on top of him wearing his hat.

As Fred MacMurray and the Indian girl ride into the fort, to warn them of the impending attack, it's plainly Fred's double who is riding the horse. He starts to dismount and then the camera switches to Fred who, again, starts to dismount.

The song, "Shall We Gather at the River?" being sung during a burial, was written in 1864, although the film takes place in 1846.

When Neal Harris is taken prisoner his shirt is ripped off of him before his hands are tied. After Shona frees him and they return to the fort he, once again, has his old, now only slightly ripped, shirt. After the Indian battle when he and Shona are preparing to leave he now has a brand new shirt.

In scenes at the White House, President James K. Polk stands in front of a US map, but the map shows the US following the Compromise of 1850. The film is set in 1846, before the Texas border was changed, before the Mexican Cession resulted in the admission of California and the organization of the Territories of Utah and New Mexico, all of which are clearly seen on that map.

Although the movie takes place in 1846, it shows the soldiers using Colt Dragoon revolvers, which weren't manufactured until 1848. The only Colt revolvers before 1848 was the Colt Patterson revolver, a small caliber 5 shot revolver which was used by the Texas Rangers.