What is this Interior Plain called that native Americans such as the Arapaho lived on (other than the Great Plains)?
Arapaho: The Arapaho ( ; in French: "Arapahos, Gens de Vache") are a tribe of Native Americans historically living on the plains of Colorado and Wyoming. Plains Indians: Plains Indians, Interior Plains Indians or Indigenous people of the Great Plains and Canadian Prairies are the Native American tribes and First Nation band governments who have traditionally lived on the greater Interior Plains (i.e. the Great Plains and the Canadian Prairies) in North America.
the Canadian Prairies