Zhao Xin was originally a marquis of Xiongnu

Xiongnu

The Xiongnu were ancient nomadic-based people that formed a state or confederation north of the agriculture-based empire of the Han Dynasty. Most of the information on the Xiongnu comes from Chinese sources...

 stock, who previously surrendered to the Han Dynasty

Han Dynasty

The Han Dynasty was the second imperial dynasty of China, preceded by the Qin Dynasty and succeeded by the Three Kingdoms . It was founded by the rebel leader Liu Bang, known posthumously as Emperor Gaozu of Han. It was briefly interrupted by the Xin Dynasty of the former regent Wang Mang...

. His name Zhao Xin was probably adopted through during his service at Han. He was one of the six generals led by Wei Qing

Wei Qing

Wei Qing , born Zheng Qing in Linfen, Shanxi, was a famous general during Han Dynasty of China, whose campaigns against the Xiongnu earned him great acclaim. He was the younger half-brother of Empress Wei Zifu, making him the the Emperor Wu's brother-in-law...

 during an expedition in 123 BC

123 BC

Year 123 BC was a year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Balearicus and Flamininus...

, and led a 3,000-strong vanguard forces along with fellow general Su Jian. Upon clashing with the Xiongnu forces, he defected back to Xiongnu, while Su Jian managed to escape after his forces were annihilated. A Xiongnu fortress named after him was constructed near the Khangai Mountains, soon after his submission to Yixixie Chanyu. That fortress was later completely destroyed by Wei Qing's forces during the finishing phase of the Battle of Mobei

Battle of Mobei

The Battle of Mobei was a military campaign fought in the northern part of the Gobi Desert. It was part of a major strategic offensive launched by the Han Dynasty in January, 119 BC, into the heartland of the nomadic Xiongnu...

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