The biggest fallacy that some people make these days is that they often consider the "modern population" living in any given place as if it is the exact same population that lived in that place at various points in history. The modern people living for example in Uzbekstan are not the same people as th people living in the age of the Timur for example because Uzbek nomadic tribes came much later to what is now called "Uzbekstan" and their earlier homeland was somewhere in Kazakhastan. Similarly before Timur the people who lived in what is now called "Uzbekstan" were yet another people the so-called "Khwarazmian" and so on and so forth. In the lands of central asia populations got replaced after every few centuries. The situation has only now changed due to modern age international border restrictions. Same is the case with most of other countries, people have been much more mobile in the past than they are credited for in every region of the world . The survival of humans in a given place was not as easy as it looks now in the modern scientific and technological prosperous age. There was no fix place for people to live for eternity in the past primitive human societies, they had to move or they were forced to move due to various social and natural causes.
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