Battle of The Little Bighorn - Military Assumptions Prior To The Battle

Military Assumptions Prior To The Battle

As the Army moved into the field on its expedition, it was operating with incorrect assumptions as to the number of Indians it would encounter. The Army's assumptions were based on inaccurate information provided by the Indian Agents that no more than 800 hostiles were in the area. The Indian Agents based the 800 number on the number of Lakota led by Sitting Bull and other leaders off the reservation in protest of US Government policies. This was a correct estimate until several weeks before the battle, when the "reservation Indians" joined Sitting Bull's ranks for the summer buffalo hunt. As one historian wrote: "The (US) Army's strength estimate didn't change, because the civilian Indian agents on the reservations didn't tell the Army that large numbers of Indians had left." Nor did the agents take into account the many thousands of "reservation Indians" who had "unofficially" left the reservation to join their "uncooperative non-reservation cousins led by Sitting Bull". The latter were those groups who had indicated that they were not going to cooperate with the US Government and live on reservation lands. Thus, Custer unknowingly faced thousands of Indians, in addition to the 800 non-reservation "hostiles". All Army plans were based on the incorrect numbers. While after the battle, Custer was severely criticized for not having accepted reinforcements and for dividing his forces, it must be understood that he had accepted the same official Government estimates of hostiles in the area which Terry and Gibbon also accepted. Historian James Donovan, states that when Custer asked Gerard his estimate on the opposition, he estimated the force at between 1,500 to 2,500 warriors.

Additionally, Custer was more concerned with preventing the escape of the Lakota and Cheyenne than with fighting them. From his own observation, as reported by his trumpeter John Martin (Martini) Custer assumed the warriors had been sleeping in on the morning of the battle, to which virtually every native account attested later, giving Custer a false estimate of what he was up against. When he and his scouts first looked down on the village from Crow's Nest across the Little Bighorn River, they could only see the herd of ponies. Looking from a hill 2.5 miles (4.0 km) away after parting with Reno's command, Custer could observe only women preparing for the day, and young boys taking thousands of horses out to graze south of the village. Custer's Crow scouts told him it was the largest native village they had ever seen. When the scouts began changing back into their native dress right before the battle, Custer released them from his command. While the village was enormous in size, Custer thought there were far fewer warriors to defend the village. He assumed most of the warriors were still asleep in their teepees.

Finally, Custer may have assumed that in the event of his encountering Native Americans, his subordinate Benteen with the pack train would quickly come to his aid. Rifle volleys were a standard way of telling supporting units to come to another unit's aid. In a subsequent official 1879 Army investigation requested by Major Reno, the Reno Board of Inquiry (RCOI), Benteen and Reno's men testified that they heard distinct rifle volleys as late as 4:30 pm during the battle.

Custer had wanted to take a day and scout the village before attacking; however, when men went back after supplies dropped by the pack train, they discovered they were being back-trailed by Indians. Reports from his scouts also revealed fresh pony tracks from ridges overlooking his formation. It became apparent that the warriors in the village were either aware of or would soon be aware of his approach. Fearing that the village would break up into small bands that he would have to chase, Custer began to prepare for an immediate attack.