Architecture of Mongolia
The Xiongnu confederation ruled present-day Mongolia from the third century BCE through the first century CE, living in portable, round tents on carts and round yurts. The Xiongnu aristocracy lived in small palaces, and their villages were protected by huge walls. S. I. Rudenko also mentions capital construction built of logs. Archaeological excavations indicate that the Xiongnu had towns; their chief city was Luut Hot (Dragon City).
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.