Existing studies on the period of the Goryeo-Khitan War have mainly focused on domestic political issues such as Goryeo’s hostile policy and northward policy towards Khitan based on the consciousness of Goguryeo’s succession in the early days of Goryeo, or the problem of the Goryeo-Khitan relationship as a unilateral international relations problem. However, this war should not be viewed only between Goryeo and Khitan, but rather through the three-dimensional dynamics of various Northeast Asian forces such as the Five Dynasties and Song Dynasty of China, Mongol, Xixia in the west and Balhae, Jeongan-guk, Jurchen in the east.
Among them, the role of Jurchen, which had strategic materials such as war horses but had not yet formed an independent unification force, cannot be ignored when considering the fact that Jurchen later defeated Khitan and grew into a hegemon of East Asia. Khitan fought against Goryeo not only for the purpose of subjugating Goryeo, and Goryeo did not fight against Khitan only for the purpose of acquiring the northern territory of Goguryeo, its homeland for nearly 30 years. Instead, they had been fighting and cooperating with each other for their respective diplomatic, military, and economic interests in the international relations of Northeast Asia, where various forces coexisted. And within that, Jurchen played an important role as a variable. Khitan came into contact with Goryeo across the Yalu River, blocking the connection route between Song and Jurchen, and used Jurchen war horses, which had been used to cultivate Song’s cavalry, to cultivate their own cavalry and gained military benefits. And by subjugating Goryeo and Jurchen, it was able to concentrate on the war against the Song in the east without any obstacles and concluded Chanyuan Treaty with Song on advantageous position, leading to diplomatic achievements that led the East Asian international order thereafter. On the other hand, Goryeo cooperated with Khitan in blocking the connection between Song and Jurchen, and mediated the trade between Song and Jurchen to gain economic benefits. During the Goryeo-Khitan War, Goryeo was able to lead the submission and cooperation of the Jurchen tribe which needed it by mediating the trade with Song, and on the contrary, Goryeo dispatched envoys who led the Jurchen delegation and was able to enhance diplomatic value by instilling the awareness to Song that Goryeo’s cooperation was necessary to gain Jurchen horses.