The Khitans conquer Balhae

Balhae had been founded in 698 on the lands of Goguryeo and the Mohe tribes, and its upper capital, near present-day Ning’an, was modelled on the Tang capital Chang’an. As the Khitans grew stronger they pushed into Liaodong: in 919 Abaoji restored the old city of Liaoyang and settled it with Chinese and Balhae households, and in 924 Balhae raided Khitan territory. On 3 January 926, according to the History of Liao, Abaoji declared that of his ‘two tasks’ one was done and only ‘the hereditary enmity with Bohai’ remained to be avenged, and set out with the empress, the crown prince Yelü Bei and his second son Deguang. Warriors from among the Uyghurs, Silla, the Tibetans, the Tanguts, the Shiwei, the Shatuo and others were later rewarded for joining the campaign.

On the night of 14 February the Khitans surrounded the Balhae prefecture of Fuyu, which fell on 17 February. On 23 February a vanguard of 10,000 horsemen routed the army of Balhae’s ‘old minister’, and that night the crown prince, Deguang and other commanders laid siege to the capital, Huhan. Dae Inseon asked for terms on 26 February and two days later came out in white, with a straw rope and leading a sheep, at the head of more than 300 officials. When thirteen Khitan envoys sent into the city to collect its weapons were killed by the guards, Dae Inseon, according to the History of Liao, rebelled again, and the city was stormed on 6 March. On 21 March Abaoji proclaimed a new era, Tianxian, and on 4 April renamed Balhae the kingdom of Dongdan and Huhan the city of Tianfu, installing Yelü Bei as its ruler with the title Renhuang wang, ‘Human Emperor-King’. Inseon and his family were taken to the Khitan capital, where a walled town was built for them, and Abaoji died of illness at Fuyu on the way home, on 6 September 926.

The History of Liao speaks of Balhae’s soldiers as numbering in the hundreds of thousands, and modern estimates of its population range from 1.5 to 4 million. Dongdan lasted only a few years: in 929 its capital and people were moved to Liaoyang, and in 930 Yelü Bei fled to the Later Tang. Balhae remnants held out in the east, in the state of Jeongan, until the end of the 10th century, while many nobles fled to Goryeo — in 934, according to the Goryeosa, the crown prince Dae Gwanghyeon arrived with tens of thousands of followers and was given the royal surname Wang. Wang Geon, who regarded Balhae as a kindred kingdom, broke with the Khitans and in 942 had the fifty camels of a Khitan embassy starved to death under a bridge. Balhae’s place in history is still disputed: Korean scholars see it as the successor of Goguryeo, Chinese scholars as a local regime of the Tang dominated by the Mohe.