So where did the Chinese peoples come from?
When I was a young buck I studied Chinese. The professors were all older gentlemen who had received their degrees in mainland China before the Reds took over, and they escaped.
They said that until then, most Chinese had a clear tribal identity within the greater Chinese identity. Among the most ancient traditions of the Han was a constant migration to the east. Many have speculated that they were moving away from the gradual desertification of central asia.
I think that's true everywhere.