stylistic:tone, linguistic:paraphrasing
Iranian theories

Most scholars agree that the Xiongnu elite may have been initially of Sogdian origin, while later switching to a Turkic language. Harold Walter Bailey proposed an Iranian origin of the Xiongnu, recognizing all of the earliest Xiongnu names of the 2nd century BC as being of the Iranian type. Central Asian scholar Christopher I. Beckwith notes that the Xiongnu name could be a cognate of Scythian, Saka and Sogdia, corresponding to a name for Eastern Iranian Scythians. According to Beckwith the Xiongnu could have contained a leading Iranian component when they started out, but more likely they had earlier been subjects of an Iranian people and learned the Iranian nomadic model from them.

In the 1994 UNESCO -published History of Civilizations of Central Asia, its editor János Harmatta claims that the royal tribes and kings of the Xiongnu bore Iranian names, that all Xiongnu words noted by the Chinese can be explained from a Scythian language, and that it is therefore clear that the majority of Xiongnu tribes spoke an Eastern Iranian language.

According to a study by Alexander Savelyev and Choongwon Jeong, published in 2020 in the journal Evolutionary Human Sciences by Cambridge University Press, "The predominant part of the Xiongnu population is likely to have spoken Turkic". However, important cultural, technological and political elements may have been transmitted by Eastern Iranian-speaking Steppe nomads: "Arguably, these Iranian-speaking groups were assimilated over time by the predominant Turkic-speaking part of the Xiongnu population".