That's when the Louisiana purchase happened
Answer: The Native American groups that lived on the Great Plains include the Blackfoot, Arapaho, Assiniboine, Cheyenne, Comanche, Crow, Gros Ventre, Kiowa, Lakota, Lipan, Plains Apache (or Kiowa Apache), Plains Cree, Plains Ojibwe, Sarsi, Nakoda (Stoney), and Tonkawa.
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temples
hope it's correct and really helps...!!