So there are various conquest dynasties in Chinese history that were founded by nomadic peoples that were not of the Han ethnicity. Most famously the Yuan and Qing Dynasties.
However some nomadic groups were able to create their own Chinese dynasties and kingdoms while not conquering the whole or most of the Chinese mainland.
A lot of these ethnicities would get absorbed into the Han peoples or be associated with the Chinese state, like Manchus and even the Mongols (there are more mongols in China than Mongolia).
One group that people don’t talk about are the Koreans. This perhaps because Koreans generally have their own independent state, then and now, and have almost never been fully incorporated into China. The exception being Koreans in Manchuria/northeast China being incorporated into the People’s Republic after World War Two.
However, we do know that in the melting pot of Manchuria/Northeast China, Korean states played a big role. Gojoseon, Buyeo, Goguryeo, and Balhae.
But these are generally considered Korean States, not Chinese oriented ones. Though it should be noted that the Goguryeo and Balhae Kingdoms were multiethnic with sizable Chinese populations.
Some may be aware of the Kingdom of Shenyang. This was a region of the Liaodong Peninsula with a large Korean population, along with Chinese, mongols, and Jurchen, during the Mongol Yuan Dynasty that various Goryeo kings ruled either alongside with Korea or before or after their kingships.
However, what about an independent Chinese state? Shenyang was considered part of the Yuan Dynasty not an indecent dynasty itself.
This is where I introduce the Northern Yan Dynasty. A Chinese Dynasty ruled by a Korean who had ties to the Goguryeo Royal Family.
Northern Yan itself was a multiethnic state since its founding emperor overthrew the previous Xianbei ruling family.
What’s interesting is that the Goguryeo Kings considered themselves to be superior to the Northern Yan Emperors while paying tribute to the Northern Yan.
The final emperor was actually executed by King Jangsu for his behavior after he fled to Goguryeo.
This is interesting as it shows the flexibility of ethnicity and national identity over time. For most of history, jurchen/Manchu were an independent people who could have entered into the modern age with an independent Manchu state/kingdom in Manchuria. It probably would have been a tributary state in the same vein as Vietnam or Korea. Instead the Manchu ethnicity was absorbed into the larger Chinese nation due to the Qing Conquest and the subsequent migration and transformation of rural Manchu farmers and semi-nomads into urban residents of major Chinese cities.
Similarly, it could have been possible for Koreans to have suffered the same fate. It could have been possible for a more militant and powerful Korean kingdom (similar to Goguryeo) to conquer or absorb enough Han Chinese to form a Korean state with a Chinese orientation that could have led to Koreans being more associated with China rather than an independent Korean peninsular state. (Shin Chae-Ho probably would have wanted a Korean state in Manchuria taking on Manchu/Jurchen characteristics though that’s a different topic for a different day)
Some sources: (I also apologize for any limited knowledge)
The Northern Yan Dynasty, a Sino-Korean State during the Sixteen Kingdoms era
byu/100Fowers inkorea
Posted by 100Fowers