As a Northwest Arkansas native I've always been interested in the Mountain Meadows Massacre. I've read every historical account I can lay my hands on. American Primeval is a historic dramatization that takes some license with known history. That said, it lets the LDS off lightly in many respects. Superstitious, illiterate LDS butchers lined up 140 men, women and children and shot them. The LDS has labored for decades to suppress the gory details of this tragedy. Governor Mike Leavitt illegally had remains buried without coroner forensics when too many children's skulls were found with close range bullet wounds. American Primeval depicts the massacre as a battlefield combat. It was a mass execution of surrendered prisoners, all but toddlers who were distributed to LDS families for rearing. Brigham Young was an illiterate bigamist with megalomaniacal designs on a theocratic empire after being propped up by the U.S. government to settle a lawless territory. The U.S. became nervous about rebellious, secessionist states in the 1850's and marched on Young's cult theocratic state. Nauvoo Legion fighters never won battles against U.S. cavalry. The sordid affair was settled by Utah's grudging acquiescence to foreswear bigamy, which they did over a period of decades. Criminal liability for the massacre ended with John B. Lee's trials and execution and the LDS's sweeping up of incriminating documentation against anybody else. Young's offer to read the sales contract to Jim Bridger is laughable. Young's secretaries wrote and read his documents for him.
I noted that period revolvers were a combination of 1851 Navies and Dragoons, though the Dragoons may have been Navies in petite hands. Many of the Army cavalrymen had Sharps carbines. Sharps enthusiasts could weigh in on whether paper cartridge breechloaders were possible in 1857, certainly not metallic cartridge versions.
American Primeval is worth viewing for its positive resolution, not the dark gory details.