As a history buff and former history teacher I have been considering it for over 50 years. Written historical records and archeological evidence have long supported the existence of slavery, citizenship, and women lacking the same agency of men, even in large pre-literate societies. Algonquin and Iroquois warriors may have practiced some egalitarian politics, but everyone knew who the badasses were who had counted coup and taken hair. Women did not participate in war councils or the religious practices with the men, and gender roles were rigid. Women and children taken in a raid of an enemy settlement would be taken into the village as a wife of a brave, even women of other races, so they were essentially chattel. Eastern Woodlands Indians were constantly at war with each other. It was the way men achieved social status.

The focus on very, very ancient hunter-gatherers in the book means that the authors can make up anything they want about them, and can skip over the warfare, head hunting, cannabilism, utter patriarchy, and other unpleasantness associated with many traditional socieities. Want to see a pre-literate traditional warrior culture? Take a close look at the Taliban.