I watched part of a show on Stonehenge yesterday and thought, “Hey, I wonder what Freepers have posted on the topic” and going down that rabbit hole somehow got me to this thread which is utterly fascinating.
Not sure what your world view is but my idea is that these are folks scattered at the Tower of Babel.
I believe the salt water flooding of the fresh water Black Sea was Noah's Flood and was the reason these people migrated to China. Also, the migrations (from this flood) up the rivers into Europe spread the Indo-European language and brought farming to Europe.
When the Black Sea flooded these farmers could no longer irrigation farm around it's edges and their farms went under 500 feet of salt water. The area around there was extremely arid and waterless.
Hundreds of thousands could live there no longer and they migrated everywhere with stories of this flood.
The Black Sea Deluge