What role and influence did the ancient immigrants in China play?

In ancient China, due to the war in the north, a large number of northerners moved south to avoid chaos, which was also an advanced science and technology, advanced political system and advanced cultural concept. From this point of view, it seems that there is a place where people can be integrated and developed, so that the economy of the south will surpass that of the north after the Song Dynasty and have a positive impact. ...