Did the Xiongnu become the Huns?
The Xiongnu have often been identified with the Huns, who populated the frontiers of Europe, starting with the writings of the French historian de Guignes in the eighteenth century. This theory remains at the level of speculation, although it is accepted by a large number of scholars including Chinese ones. DNA testing of Hun remains has not proven conclusive in determining the origin of the Huns. The name Xiongnu sounds similar to the name "Hun". (For example, the country Hungary is translated in Chinese as "Xiongyali".) A variation to Xiongnu is Hsiung-nu, which looks very similar (in English) to the "Huns".
It is interesting to note that a different reading of the word ýÖ (Xiong) can be found in those Chinese dialects that preserve ancient pronunciations, such as Cantonese, i.e., /hʊ©¯/. It could lend credence to the theory that the Huns were in fact descendants of the Western Xiongnu who migrated westward, or that the Huns were using a name borrowed from the Western Xiongnu, or that these Xiongnu made up part of the Hun confederation. In the 1998 Walt Disney animated film Mulan, the invaders of China in the original English version of the film were called the Huns, while in the Cantonese and Mandarin versions of the film, they were referred to as the Xiongnu.
The legendary folk-tales of Hmong from Vietnam
According to the theory of Hmong communities in Vietnam, the ancient Xiongnu were actually a group of Hmong being, at that particular time, ruled by sage of that clan and therefore called themselves so. There are some folk-tales facts that support so. The Hmong people once inhabited the area near Manchuria according to folk-tales about 5,000 years ago. It could have been that some became or joined with the Xiongnu. Ultimately, though, after their defeat of semi-mythological battle at the Zhuolu Plains and the death of their leader Chi You (who said to be a beast) they fled southward through China and Vietnam, although some of them stayed in about the times of Yellow Emperor. It could have been these that regrouped and became the Xiongnu.
Huns became mixed when they got to Europe [as a hodge-podge of all the tribes they swept before and with them]. The Hsiung-nu tribal group Sima Qian was describing was not particularly mixed - a Chinese historian would surely make a prominent note of that.