Xiongnu
The Xiongnu () were a confederation of nomadic peoples who, according to ancient Chinese sources, inhabited the eastern Asian Steppe from the 3rd century BC to the late 1st century AD. Chinese sources report that Modu Chanyu, the supreme leader after 209 BC, founded the Xiongnu Empire.
Han–Xiongnu War
Due to the many losses inflicted on the Xiongnu, rebellion soon broke out and former enslaved people rose up in arms. Around 80 BC, the Xiongnu attacked the Wusun in a punitive campaign and soon the Wusun monarch requested military support from the Han empire. In 72 BC, the joint forces of the Wusun and Han invaded the territory of the Luli King of the Right. Around 40,000 Xiongnu people and many of their livestock were captured before their city was sacked after the battle. The very next year, various tribes invaded and raided the Xiongnu territory from all fronts; Wusun from the west, Dingling from the north, and Wuhuan from the east. The Han forces had set out in five columns and invaded from the south. According to "Hanshu", this event marks the beginning of Xiongnu decline and the dismantlement of the confederation.