Much of human culture derives from the environment within which man lives. The so-called "Plains Indians" began as sedentary semi-agrarian society that evolved into nomadic society, once it came in contact with European colonials and the earth-shattering technology of tamed horses. Horses allowed for these sedentary social units to be able to chase heavier game of American bison in the plains, transforming once the sedentary culture (and its religious mythos) into nomadic culture (and subsequent shifting of its religious mythos to more nomadic paradigm).

Climate variations differ significantly in longitudinal rather than latitudinal direction. Thus, the ease of technological and cultural exchange in East-West axis (following possibility of crop and livestock transplantation) compared with the inordinately difficult travel between North-South axis. Also, the courses and nature of rivers determined the possibility of technological exchange, and thus, progress of civilization.