Xia

The Xia of Helian Bobo, called Hu Xia to distinguish it from the Xia of Yu the Great, was the last and most forbidding of the Sixteen Kingdoms, a Xiongnu state raised on the Ordos frontier. Its founder, born Liu Bobo, son of a murdered Tiefu chieftain, served Later Qin as a general before murdering his father-in-law, seizing his troops, and proclaiming himself Heavenly King in 407, changing his surname to Helian, majestic as the sky. He built his capital Tongwan on the Wuding River, a white-walled fortress raised by a hundred thousand conscripts whose ruins still stand, the only Xiongnu capital ever found. In 418, while the Jin general Liu Yu withdrew from his conquest of Later Qin, Helian Bobo slipped in, took Chang'an, and proclaimed himself emperor on the Ba plateau. His reign was terror by design: weapons were tested on the workmen, and cruelty, he said, makes subjects look up. At his death in 425 his sons killed each other over the succession, and the survivors could not hold both capitals. Northern Wei took Tongwan in 427 and Chang'an soon after; the last ruler, Helian Ding, destroyed Western Qin in 430 before the Tuyuhun captured him in 431 and sent him to the Wei executioner. Twenty-five years, three rulers, and a white city in the desert were all that remained of the Tiefu empire.