We stayed at 7th Ranch RV Park in Garryowen MT last year when we visited the area. My husband was fascinated by the history of the area. We walked several of the locations while he tried to fix events in his mind. He reads a lot of the history of the area and the era. We did not see the film referenced above, but did not get the same impression of the area as the poster above.
For myself, I found it to be a most depressing place, due to the feeling of senseless loss of life.