View attachment 216456
From this map, you can easily distinguish the four layers of affinity .
First Layer: Regions between the Yellow river and the Yangtze River, aka the core of China and origin of the Chinese and Chinese culture. The political center gradually shifted to Beijing in the second millennia from Xi'an in the first millennia.
Second layer: Regions south of the Yangtze river, the Chinese economic center gradually shifted to southeastern China from northern China during the second millennia while the political center remains in the north. The southern Chinese are genetically different from northern Chinese at the beginning and they keep their various unique languages which are mostly indistinguishable to Mandarin to even today.
Third layer: Manchuria in the northeast and Xinjiang in the northwest.
Xinjiang region long serves as a contending arena of various Chinese dynasties and nomads such as Xiongnu and Turks from the Mongolian steppe and is also key pass to the Silk Road during the first millennia. Xinjiang region was considered more strategically vital than other frontier regions. The Islamization of Xinjiang fundamentally changed the culture of Xinjiang and obviously alienates it from the Chinese culture. Manchuria is usually the land of exile for the vanquished until the rise of the sinicized Jurchen and later Manchu people. These regions are ultimately pulled into Chinese orbit during the second millennia.
Fourth layer: Tibet and Mongolia. Both regions were closely linked to each other. These regions are believed to be uninhabitable and their cultures are exotic to traditional Chinese culture. During the past 500 years, Beijing used various methods to pacify these regions and effectively reduced their population to negligible.