Fort Kearny, where the 1st Nebraska Cavalry troops are stationed in the movie, was an actual U.S. army post located on the south bank of the Platte River. It is inactive, but still stands and is a Nebraska state historical park. A half-mile to the east is Fort Kearny State Recreation Area, which contains a small lake and numerous camping sites.
The area where this movie is set, south central Nebraska, was at the time referred to as the "Great American Desert", due to a lack of forestation and ground water. However, lying just below the surface is the Oglalla Aquifer, one of the world's largest underground water tables, in the south central Nebraska region, where the water table may be as close as six feet below the ground. Tapping the Oglalla Aquifer, along with irrigation from numerous small rivers, transformed the Great American Desert into a highly productive agricultural area.
Three of the rivers mentioned in the movie--The Little Blue River, The Elkhorn River and The Loup River--actually exist, but they are not close to the real Fort Kearny. The closest, The Loup River, is located over 60 miles from Fort Kearny. The Little Blue River would be about 100 miles from Fort Kearny, and the Elkhorn River is just west of Omaha, over 150 miles east of Fort Kearny.
Fort Kearny is located on the south bank of the Platte River in what is now Kearney County, NE. The different spelling of the fort and the county is intentional. When Nebraska counties were organized after statehood in 1867, the City of Kearney (population 32,425) was across the Platte River in Buffalo County, Nebraska.
Opening credits: The characters and incidents portrayed and the names used herein are fictitious, and any similarity to the name, character or history of any person is entirely accidental and unintentional.