According to the Book of Zhou and the History of the Northern Dynasties, the Ashina clan was a component of the Xiongnu confederation,[REF][REF] but this connection is disputed,[REF] and according to the Book of Sui and the Tongdian, they were "mixed Hu (barbarians)" () from Pingliang [REF].
As part of the heterogeneous Rouran Khaganate, the Türks lived for generations north of the Altai Mountains, where they 'engaged in metal working for the Rouran' [REF].