Most people have a nationalistic sense of pride, especially those living in Missouri, and that’s why history has taught us that Europeans who swept into North America wiped out the Native Americans with superior technology and greater firepower. Unfortunately, you can’t exaggerate reality. Native Americans were mostly wiped out by disease inadvertently transferred from European settlers, and that easily paved the way for most of the expansion that occurred during the early centuries of colonization–so much more so than technology could.
In later centuries, the Native American tribes became more fragmented as a result of the widespread death that had already ravaged their way of life. This affected the path to expansion during events like the Black Hills Expedition led by Custer.
When the Fort Laramie Treaty of 1868 was broken by the U.S. government, the resulting conflict called the Great Sioux War lasted only a short while from 1876 to 1877, although skirmishes lasted for years afterward. It may have lasted longer or cost the American settlers and army a lot more, but the fragmentation within the Sioux Nation resulted in different factions–some who fought, and others who openly embraced peace.
Although the Sioux who chose to fight believed in their cause and knew the lay of the land, they held no advantage in numbers. At this point in time, the difference in weaponry might not be what most people would expect. While most records suggest that the Native Americans were still using traditional bow and arrow during most engagements, we also know that a plethora of firearms was in use as well. Arms used by the Sioux in some battles–such as the famed Battle of Little Bighorn–may have even been superior to those used by the U.S. military.
The soldiers of the U.S. army were equipped with .45 caliber, single-action revolvers. For long range, they used the 1873 Springfield Model rifle–widely believed to grant them superior range over their Sioux adversaries.
This may have been true some of the time, but perhaps not always. The Battle of Little Bighorn took place only a year before the Great Sioux War broke out, and archaeological excavations during the 1980s managed to rip 2,361 cartridges from the dirt. These came from 45 different kinds of firearms, confirming the idea that the Native Americans were using them too. It also proves that members of the U.S. army often carried their own weapons.
Survivors of the battle claimed that the Native Americans who slaughtered the rest of the 7th Cavalry that day were armed with repeating rifles, Winchesters in particular. This provided the Native Americans with a tremendous advantage in firepower, while superior numbers and the utter stupidity of Custer certainly helped win them the day.
During most battles of the Great Sioux War, though, it seems likely that weaponry was probably on par to that used by the U.S. military. We can’t hope to hold accounts during the period in high regard, so it’s impossible to be 100 percent accurate.
It seems that the Great Sioux War was lost to the U.S. army because it seemed a cause not worth fighting anymore, as the American expansion then seemed inexorable. The wave was coming to swallow their way of life, and no one could hope to stop it. This was the reason why memorable figures of the time period such as Sioux Chief Spotted Tail chose to help white men pursue peace rather than war. Weapons used during the war probably had little to do with the outcome.