What people or tribes bordered the Xiongnu to the north?

To the north of the Xiongnu, various groups and tribes included the Siberian nomadic peoples, such as the Donghu and the various Turkic tribes. These groups were often in flux and engaged in trade, conflict, or alliances with the Xiongnu. The geographical region was characterized by a diverse array of cultures and tribes, contributing to the complex dynamics of the steppe. Additionally, the Xiongnu's northern neighbors were influenced by the broader interactions of the Eurasian nomadic cultures.