For hundreds of thousands of years, it was the only system.

"At first it was like the proverbial biblical cloud “no bigger than a man’s hand” — the activities of seemingly insignificant nomadic bands roaming the less desirable fringe areas of our globe seeking grass for their herds. Over millennia they were apparently out there in the harsh, unwanted, colder, sparser territories on the edges of the earth, while the first great agricultural civilizations spread out along the lakes and rivers in the fertile heartlands. To these agricultural peoples, enjoying humanity’s early peak of evolution, peace, and prosperity must have seemed the blessed eternal state for humankind, the nomads no more than a peripheral novelty.

We have nothing to go by but speculation on how these nomadic bands grew in numbers and in ferocity and over what span of time.4 But by the fifth millennium B.C.E., or about seven thousand years ago, we begin to find evidence of what Mellaart calls a pattern of disruption of the old Neolithic cultures in the Near East.5 Archaeological remains indicate clear signs of stress by this time in many territories. There is evidence of invasions, natural catastrophes, and sometimes both, causing large-scale destruction and dislocation. In many areas the old painted pottery traditions disappear. Bit by devastating bit, a period of cultural regression and stagnation sets in. Finally, during this time of mounting chaos the development of civilization comes to a standstill. As Mellaart writes, it will be another two thousand years before the civilizations of Sumer and Egypt emerge.6 "

Eisler, Riane. The Chalice and the Blade (p. 84). HarperCollins. Kindle Edition.