Noin-Ula burial site
Many immigrants lived in the Xiongnu pasturelands, but at first they did not mix with the Xiongnu. To be a Xiongnu, one had to be a member of a clan, born of Xiongnu parents. The newcomers were well off, but were outsiders, and could marry only among themselves, not the Xiongnu. Only later did they intermix, increase in numbers, even created a state that existed from 318 to 350 AD.
Xiongnu
The supposed Old Chinese sound of the first character (匈) has a possible similarity with the name "Hun" in European languages. The second character (奴) appears to have no parallel in Western terminology. Whether the similarity is evidence of kinship or mere coincidence is hard to tell. It could lend credence to the theory that the Huns were in fact descendants of the Northern Xiongnu who migrated westward, or that the Huns were using a name borrowed from the Northern Xiongnu, or that these Xiongnu made up part of the Hun confederation.