Factual error: When Eakins returns to the house after he swears an oath to the union. You can see a thermostat on the wall behind him. (01:40:00)
Factual error: In the hanging scene where the drummer boy is playing, the drummer is using "matched grip" which is a concert style of playing a snare drum. The grip used for a marching drum in the Revolutionary or Civil War would be "traditional grip" (as we call it today), which allows the left hand to match the angle of the drum, which was tilted to the right -so each hand grips the stick differently. During those times, slings were used over the shoulder to support the drum and the drum would rest on the left leg. At the end of the movie there is a still shot of a drummer boy using traditional grip.
