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.
Han–Xiongnu War
As the Xiongnu economic and military situation deteriorated, the Xiongnu were willing to renew peace during the reigns of Huyandi Chanyu (r. 85-69 BC) and Xulüquanqu Chanyu (r. 68-60 BC), but the Han court gave only one option, tributary submission. After Xulüquanqu Chanyu's death in 60 BC, a Xiongnu civil war broke loose in 57 BC over the succession, which fully fragmented the Xiongnu confederation with many contenders. In the end, only Zhizhi Chanyu and Huhanye Chanyu survived the struggle to power. After Zhizhi Chanyu (r. 56–36 BC) had inflicted serious losses against his rival Huhanye Chanyu (r. 58–31 BC), Huhanye and his supporters debated whether to request military protection and become a Han vassal. In 53 BC, Huhanye decided to do so and surrendered to the reign of the Han empire.