Ordos Plateau
In Chinese accounts, the Xiongnu first appear at Ordos in the "Yizhoushu" and "Shanhaijing" during the Warring States period before it was occupied by Qin and Zhao. It is generally thought to be their homeland, however when exactly they came to occupy the region is unclear, and it might have been much earlier than traditionally thought, as suggested by archaeological finds. As the Xiongnu expanded southward into Yuezhi territory around 160 BC under their leader Modun, the Yuezhi in turn defeated the Sakas (Scythians) and pushed them away at the Issyk Kul. It is thought the Xiongnu also occupied the Ordos area during the same period, when they came in direct contact with the Chinese. From there, the Xiongnu conducted numerous devastating raids into Chinese territory (167, 158, 142, 129 BC). The Han Dynasty started to fight the Xiongnu in the 2nd century BC under emperor Han Wudi, and colonized the area of the Ordos under Shuofang commandery in 127 BC. Prior to the campaign, there were already commanderies established earlier by Qin and Zhao until they were overrun by the Xiongnu in 209 BC.
Jin Midi
Jin Midi was born in 134 BC to a royal Xiongnu family. He was the heir apparent to Xiongnu's Prince of Xiutu, one of the major princes under the supreme ruler of the Xiongnu, the "Chanyu" Gunchen. After Gunchen's death in 126 BC, his brother Ichise succeeded him. During this time, the Prince of Xiutu and another major prince, the Prince of Hunye, were responsible for defending Xiongnu's southwestern border with Han Dynasty – modern central and western Gansu.