Another perspective to keep in mind, and this is not true for all indigenous peoples of course, is that a lot of Indigenous knowledge was/ is shared verbally and not always documented in writing like anthropological textbooks, as many colonial settler cultures tend to do.

A lot of indigenous history is explicitly not communicated to colonial cultures, researchers, anthropologists, etc… as to protect their culture from the people that displaced and slaughtered them.

Sorry this probably isn’t the research/ content you were looking for!

Some other tribes native to the Yellowstone NP area, incase you want to do more research on them :) Newe Sogobia (Eastern Shoshone) Cayuse, Umatilla and Walla Walla Apsáalooke (Crow) Tséstho’e (Cheyenne)