The foundation’s Research Division 2 carries out studies on relations and exchanges among countries in Northeast Asia, where conflict and coexistence have continued from the Goryeo, Song, Liao and Japanese dynasties of the 10th century to the nations of that presently make up the region – Korea, China, Japan, Russia and Mongolia. In particular, the nature of the tribute system that defined the traditional relationship among the Northeast Asian countries will be studied, along with the differing versions of the system that were practiced in different regions and eras. We will also examine how the tribute system evolved into the modern international legal system. Furthermore, by focusing on the Manchurian region—also referred to as ‘Northern China’ or ‘the Northeast’—where each Northeast Asian nation has a stake, we hope to create a new perspective on the history of Northeast Asian interrelations. Also, studies on territorial and borderline issues originating from the boundaries of different national, ethnic and racial identities will be conducted, which will hopefully lead to a state of peaceful coexistence for all Northeast Asian countries.

Relations between Korea and China were more complicated during the Goryeo than in any other period in history. During this period, Goryeo’s relationship with Song, founded by the native Han Chinese, was crucial, but in political terms, relations with Liao (founded by the Khitans) and with Jin (founded by the Jurchens)—both ethnic groups from northern China—were equally significant. Moreover, toward the end of the Goryeo period, foreign relations were mainly focused on its relationship with Yuan, the Mongolian dynasty that eventually dominated all of China. A reexamination of Korea’s relationship with China during this period is called for, based on a new interpretation of international relations in Northeast Asia in the context of the changes in Goryeo’s relations with Han and the northern ethnic Chinese groups.

918	Founding of Goryeo; diplomatic envoy dispatched to the Khitans; Hu Baekje (Later Baekje) sends envoy to Chinese kingdom of Wuyue
960	Establishment of Song China
962	Goryeo’s envoy dispatched to Song
993	Khitans’ first invasion of Goryeo; General Seo Hui of Goryeo and the Khitan General Xiao Sunning conclude peace agreement through skilful diplomatic maneuvering; Goryeo adopts the Khitan reign name the following year
994	Goryeo requests cooperation from Song in launching an attack against Khitan but is refused
1010	Second Khitan invasion of Goryeo
1107	Commander Yun Gwan sends a punitive expedition against the Jurchen and constructs the Nine Forts in the Northern Border Region the following year.
1115	Jurchen leader Wanyan Aguda proclaims himself emperor of the newly established Jin Dynasty
1125	Downfall of Liao; Goryeo consents to enter into a suzerain-subject relationship with Jin the following year
1206	Establishment of the Mongol Empire by Temujin
1218	Khitan troops from the fallen Liao Dynasty invade Goryeo; Mongols and Goryeo join forces against the Khitans at Gangdong Fortress
1225	Mongol envoy Chu-ku-yu killed near the Yalu River; Goryeo and the Mongols breach their relationship
1231	First invasion of Goryeo by the Mongols; invasion continues sporadically until 1260
1260	Peace reached with the Mongols
1274	First expedition of combined Goryeo-Yuan forces against Japan
1281	Second expedition against Japan
1368	Founding of Ming China; King Gongmin of Goryeo establishes diplomatic ties with the Ming
1392	Collapse of Goryeo; founding of Joseon; envoy dispatched to Ming China the following year

The Mongols originated in the steppe region of central Eurasia in the 13th century and, within a few generations, went on to build one of the most powerful empires in history under the command of the legendary leader Ghengis Khan. The Mongolian Empire unified a vast region from the Pacific to Eastern Europe, expediting exchange between the cultures of the East and the West.

At the time of the Mongol invasions, Goryeo was ruled by a military regime however, despite decades of struggle, Goryeo ultimately fell to the Mongols. That being said, Goryeo was able to maintain its own governing system as a kingdom within the Mongol Empire unlike other states such as Western Xia of the Tangut, Southern Song, the Khara Khitai in Central Asia and Khwarazm.

Between the mid-13th and mid-14th centuries, the Mongols’ Yuan Dynasty implemented its interference policy in Goryeo. Goryeo’s kings took Mongolian princesses as their queens, which gave Goryeo privileges as a “son-in-law nation” but actually lowered the status of the kingdom overall. During this period, Goryeo kings were required to shuttle back and forth between Khanbaliq (modern Beijing) and Gaegyeong. In the case of King Chungseon, for example, he spent his entire reign in the Mongolian capital.

After conquering Southern Song, the Mongols launched two campaigns against Japan, but failed in the face of storms at sea.

The Yuan Dynasty ruled China for a century until 1368, when Zhu Yuanzhang drove the Mongols out to the northern regions and established Ming, a dynasty of the Han Chinese lineage. At that time, the Mongols founded the short-lived Northern Yuan.

Meanwhile in Goryeo, King Gongmin had already eliminated pro-Mongol factions, thereby ending Mongol interference in the kingdom by the 1350s.

20th century, BC	Inhabited Mongolian steppe region as nomads
Mid-4th-mid-6th century	Rouran tribe rules Mongolian region
Mid-6th century	Turks rule Mongolian region
Mid-8th century	Weiwuer tribe rules Mongolian region
1162	Temujin born
1206	Temujin unifies Mongolia; takes the title Ghengis Khan
1234	Mongols conquer Jin Dynasty
1231	Mongols’ 1st attack on Goryeo
1251	Tripitaka Koreana completed
1260	Kublai (1260-94) crowned as Khan
1271	Sets up capital in present-day Beijing; takes Yuan as dynasty name
1272	Yuan conquers Southern Song
1274, 1281	Two campaigns launched in attempt to conquer Japan; both fail due to sea storms
1356	Eastern Expedition Field Headquarters closed down
1368	Fall of Yuan