Goryeo's Foreign Policy Analyzed through Wars against the Khitans
The Khitans emerged as a new powerhouse in Northeast Asia during the chaotic, final period of the Tang Dynasty. Yelu Abaoji founded Khitan in 916, calling himself the emperor, and in 926 he overthrew Balhae. His immediate successor, Taizong Yelu Deguang, brought the later Tang Dynasty to the ground in 928, allowing Governor Shi Jingtang to establish the Later Jin. Khitan occupied the 16 states, thus allowing them to emerge as a powerful authority in the northern region.
The relationship between Goryeo and Khitan dates back to the year 922 (the 5th year of Taejo). Goryeo had been hostile towards Khitan because Balhae, its brother country, was overthrown by the Khitan. Thus, in the year 942 (the 25th year of Taejo), when the Khitan envoys visited Goryeo with 50 camels, King Taejo exiled the 30 envoys and starved the camels to death under the Manbu Bridge. The Khitans had sent camels as a gift to promote goodwill and friendship between themselves and Goryeo. The gift had really been sent with the intention to remove the threat that Goryeo posed, as a war between the Khitans and the Later Jin was on the horizon. Eventually, the Later Jin was brought down by Khitan in the year 946. King Taejo had intended to recapture Goguryeo’s older land after unifying the Later Three Kingdoms, however his dream was shattered because the Khitans had invaded Balhae first. Thus, King Taejo's target for attack shifted from Balhae to Khitan. King Taejo tried to take Balhae by forming a connection with Goguryeo. However, the Khitans took no retaliatory measures against King Taejo’s anti-Khitan actions because of its looming battle against the Later Jin.
Since its foundation, Goryeo continued its northward policy, reaching the Yalu River basin in the period of King Seongjeong. At the time, the Khitans built castles in Wigu, Jinhwa and Naewon (presumed to be Geumdongdo near Yalu River) along the Yalu River to ward off Goryeo’s further advances. As Goryeo and Khitan met head-on in the Yalu River basin, war clouds began to gather.
Lee Jeong-shin(Emeritus Professor of History at Hannam University )