The most sad question which I get from visitors to the Custer Battlefield Museum is a simple one:
"What were all the Indians doing together? Why were all the tribes in the same place?"
This question is interesting to me, and strikes me as the root problem that people encounter while attempting to understand the Battle of the Little Big Horn. The question has many answers, so let us begin with surface level explanations. Official accounts from Sioux, Cheyenne, and Arapaho traditions state that the Native Americans travelled to the banks of the Little Big Horn and set up camp after hearing of a large herd of antelope nearby. A "larger" answer to the question: the Sioux, Cheyenne, and Arapaho had moved into the Powder River Country (and regions further north) in order to take advantage of treaty provisions, which gave them access to the vaguely-organized Unceded Territories in the Montana and Dakota territories as hunting grounds. As buffalo on the plains grew scarce, these remaining independent tribes often found themselves hunting and sharing territory in unprecedented ways. As is always the case when speaking about cultural groups, there is no absolute "rule" for how these interactions played out; in the case of the Little Big Horn encampment, the individual tribes were able to function in shared camps due to the strength of age old alliances, resource necessity, and the powerful presence of Sitting Bull, who's medicine at the time of the gathering was seen to be some of the most stable and impressive in Sioux history.
Now lets zoom out. We have a surface level, academic answer, that satisfies the factual requirements and which flesh out the actions of the Sioux, Cheyenne, and Arapaho peoples in the days leading up to Custer's defeat. The real answer to the question, in my mind, is also simple, albeit tragic and, in some sense, numbing:
The Native Americans encamped on the banks of the Little Big Horn river, in June of 1876, were merely living.
They had no motive. They were not organizing as a form of formal protest, or gathering in order to make a statement or a stand against the encroachment of settlers, nor were they gathering as a basis for a military expedition (in any organized, society-wide sense). Each of these presuppositions which people bring to our museum are wrong, and in bringing these incorrect assumptions into a study of the Battle of the Little Big Horn, people miss what is, in my mind, a crucial aspect of the battle.
George Armstrong Custer, the American icon who made a name for himself by riding at the fore of brash, bloodthirsty cavalry charges, deliberately attacked a civilian gathering as a fully-empowered agent of the United States government, and, as was his custom, proceeded with every intention of cutting warriors off from their families, taking hostages, and killing nearly indiscriminately in order to garner a sufficient margin of victory.
George Armstrong Custer had used this take-no-prisoners approach to Indian warfare before. At the Battle of the Washita, 1868, Custer and the 7th Cavalry surrounded, surprised, and slaughtered a group of Cheyenne led by Black Kettle, a respected advocate for peace within the Cheyenne tribe. The Cheyenne group believed that they were living under the protection of a nearby US Fort. Casualty estimates for the "battle" vary, but a general consensus puts the number of non-combatant dead (women, children, and the elderly) between one-third and one-half of the entire casualty count. Custer proceeded to burn the camp and all the possessions left within, slaughter a herd of around 800 Indian ponies, and then withdraw his troops (and the remainder of the camp, now prisoners) in order to report back an inflated Indian body count. The military establishment of the day viewed this methodology of surprise attacks against stationary camps as extremely effective, even commendable; Custer was widely celebrated as an accomplished Indian fighter following this slaughter, a bloody lesson about the value of Indian life in the eyes of US Army leaders.
Now, on to the battle itself. Prior to the Battle of Little Big Horn, Custer divided his command into three detachments. He ordered Major Reno into the valley below with companies A,G, and M, with instructions to launch a direct attack on the unsuspecting encampment. One can only imagine the horror that took place in those moments: Reno's troops dismount, quickly form a skirmish line, and prepare to fire a volley into the surging, panicking mass of humanity, which was engaged just moments before in the peaceful pursuits of a lazy summer afternoon. Reno's troops fire, again and again; Springfield bullets smash into teepees, ponies, possessions, women, children. According to validated testimony, two wives and three daughters of the famed warrior Gall were killed in Reno's initial assault, his entire family, and he was by no means the only one to suffer such needless tragedy in those opening minutes. The callused command to fire on such a defenseless position speaks volumes about Custer's priorities in the battle; the rage and thirst for revenge that must have seized the hearts and minds of the Sioux, Cheyenne, and Arapaho warriors after this attack is, truly, unfathomable.
Eyewitness testimony states that later in the battle Custer, after dividing his third of the command again along Battle Ridge, attempted to ford the Little Big Horn River and take two companies directly into Sitting Bull's encampment. Scholars of the battle agree that Custer was most likely attempting to get in between warriors outside the camp and the noncombatants still within, which included women, children, and the elderly. If this hypothesis is correct (all evidence suggests that it is), than it's more than reasonable to conclude that Custer was planning to use the captured noncombatants as a deterrent against further attacks from the warriors. Had Custer succeeded in his plan, it's almost certain that noncombatant casualties would have risen, as the 7th Cavalry had little to no regard for indigenous life in the heat of battle (as evidenced by the previous instances).
These facts help underscore the realities of both Custer as a commander and of the Indian Wars in general. Total war was encouraged, celebrated as the only method by which the warriors of the northern plains could be subdued; Sioux, Arapaho, and Cheyenne noncombatants (along with those of countless other tribes) often suffered horribly in the US Army's pursuit of Indian removal, and the Army's value of plains Indian life was despicably low. It's a sordid reality, friends, and it must be understood in order to understand the true magnitude of the Battle of the Little Big Horn.