The oldest known civilization is not the civilization of the Indus River Valley, as is still claimed in most history textbooks, but the Afro-Asiatic civilization which extended from the Atlantic coast of modern Nigeria to the Indus River Valley. The disciplines of linguistics, anthropology, genetics and archaeology contribute to our understanding of how the Afro-Asiatc worldview diffused across this vast expanse of land.
The diffusion was driven by three factors: migration out of Africa, commerce, and the marriage alliances of Afro-Asiatic chiefs. These chiefs had 2 wives. Abraham's 2 wives produced 6 sons. If each of these sons had 2 wives, the population of Afro-Asiatic nobles would have expanded very quickly. Each chief needed to locate where he could establish his own territory. This drove the eastward expansion of the Afro-Asiatic Dominion.
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