The population of the Pacific Slope was in reality more dense than that of the Pueblo culture. Almost all of the Apacheans arrived in the southwest about A.D. 1500. So, just prior to that, the Pueblos owned considerably more territory thereby making their population less dense.

A major contributing factor to the dense Pacific Slope and Pueblo regions was the relative peaceful nature of the inhabitants. Violence tended to increase on the Pacific Slope, however, the more northward one traveled, but so did the richness of the environment with runs of salmon and bountiful food resources. All of the inhabitants of the Pacific Slope were hunter/gatherers.

There was no shortage of food resources in the Eastern Woodlands. Augmenting that, most the inhabiting ethnies were sedentary and farmed corn, squash, and beans. But there was a near constant state of war in the Eastern Woodlands. Whether it was counting coup, revenge, or all out warfare, every ethnie was affected. Evidence of this condition rests in oral traditions, observations of early European observers, and the widespread existence of polygamy.

The Great Plains were virtually uninhabited until about 1650. There were some Plains River cultures, mostly Caddoan speakers, but their lifestyle and culture was the same as that of the Eastern Woodlands. They too were sedentary farmers. Their populations are considered to be Eastern Woodlands herein.

The arid Northwestern Plateau and Great Basin were inhabited by hunter/gatherers and foragers respectively. The environment offered little opportunity for dense populations. Though there was farming in the Southwestern Desert, much of the terrain was totally inhospitable. The late arriving Apacheans were at first predatory hunter/gatherers.