>>/40644/
The fertile lands around the yellow river and the other rivers in that area could support large populations and those large populations gradually subjugated the others. Most of China is actually pretty barren so the Chinese empires just expanded into these areas as well. They could never really get that far northwards though. After a while they managed to subjugate the south which is also a fairly populous region.
>>/40647/
Sure but it's applicable to nomads in General.
...It's not wrong that is what they are.