Factual error: The events depicted in the movie occur around the time of the California gold rush in 1848, yet every man and his dog wields an 1873 Colt Peacemaker.
Factual error: All the couples on the train are modern and not correct for the period. Trackwork back then wasn't very good, considering the speed that the back end of the train is going it probably would have derailed long before it did. The caboose and the rest of the train seen to be just shunted off the track for the dramatic crash, realistically it would have flipped over and gone over the trestle.
Factual error: When Tom is singing "If You're Ever Down In Texas" to the cowgirl, Jerry winds the crank on the Victrola counter clockwise.
Factual error: The Welsh Guards parading at the start of the film weren't formed until 1915. The film is set in 1872.
Factual error: Raquel Welch is shown to have modern tooth fillings during the rape scene.
Factual error: There appears to be a pickup truck parked by a barn in the background when Steve McQueen is standing by his horse, talking to Linda Evans. (00:19:00 - 00:20:00)
Factual error: This movie takes place post-civil war, and Fisher, in his first discussion with General Cortinas refers to the "Republic of Texas" being ripe for the taking. Texas ceased to be a republic in 1845, when it joined the United States.
Factual error: When Buster joins the card game in the saloon, he looks at the hand of the player that had just left. Given the circumstances in the saloon, the cards cannot be spot clean and white as fresh snow. Also, they seem to be plastic cards, which did not exist yet back then.
Factual error: On their journey, Rooster is bragging about his navy colts, when actually his sidearm is a Colt .45 Peacemaker, also known as an Army Colt M1873.
Factual error: All the troops in the Fetterman massacre are cavalry. In fact, the majority of the detachment, including Fetterman himself, were infantry.
Factual error: When Pauline is burying her husband in the cemetery there is a shot of a mountain with vultures swarming around it and an antenna mast is visible on top of the mountain. (00:24:18)
Factual error: The train's locomotive has a steel cab, an electric headlight, and other modern applications. Overall, it more closely resembles an early 20th century steam engine than that of the 1880's, when the movie supposedly takes place.
Factual error: When Mrs. Lane screams at the sight of the horse, on the back of Karen Steele you can see the outline of a modern bra under the shirt. (00:23:30)
Factual error: When Cagney surprises Ward Bond in a saloon, they run out the back and across a rail freight yard. They jump onto boxcars of a slow moving train. Bond jumps up between two older wooden-bodied boxcars, A and B. Cagney, in pursuit, jumps up between cars B and C. In the wide shots, car C is seen to be a steel-bodied boxcar built at the earliest in the late 1930's. Events in the movie show the time-line to be set in September, 1893.
Factual error: It's winter in Montana, yet there are rattlesnakes out in the cold.
Factual error: John Grady Cole's father says that the last time he spoke with Cole's mother was in San Diego in 1942. His lighter has a 3rd Infantry Division badge which means he fought in the European theater of WW2, not the Pacific Theater.
Factual error: Waco Johnny Dean played by Dan Duryea grabs a pistol from a bystander and then gets shot multiple times by Jimmy Stewart. As Waco goes down he fires several rapid fire shots from a double action revolver. Not likely given the time period some time after the civil war.
Factual error: In any number of scenes in this movie characters are seen wearing celluloid badges in support of statehood for Wyoming. This movie is set in the year 1890 and the process of making celluloid badges wasn't developed until 1896.
Factual error: When Brennan rides into town, behind the stage coach in the back street there is a pick up truck parked.
Factual error: The US Cavalry are careful not to run into Confederate cavalry from Fort Davis, who are shown in the distance. Fort Davis was indeed occupied by the Confederates from 1861 to 1862, but was then abandoned until 1867. The film is set in 1864, so there would be no Confederate troops at Fort Davis.