뉴스레터

The account of King Jangsu's
accession to the throne found in
the Oksan Academy Edition of
History of the Three Kingdoms
(1537)

King Jangsu (413-491), the twentieth king of Koguryo, was on the throne for seventy-nine years. It is said that he was ninety-eight years old when he died. Hence his posthumous name Jangsu (長壽), which means longevity. The period of his reign, the fifth century, was an era of turbulence for East Asia. China at the time was in the period of the Northern and Southern Dynasties. In northern China, the Northern Wei Dynasty established by the Tuoba clan of the Xianbei had expanded its power and become a threat to its neighboring countries. Most of the accounts of the King Jangsu era included in History of the Three Kingdoms are about Koguryo's dispatch of envoys to Northern Wei. Why was that?

King Jangsu had many achievements, but most notably, he had excellent diplomatic abilities, which prevented Koguryo from getting caught up in great wars during his reign. Otherwise, it would have been difficult for Koguryo to create its independent society and culture in its new capital of Pyeongyang. The diplomatic encounter between Koguryo and Northern Wei has something to do with the matter of Northern Yan (北燕) in the Liaoxi region.

Making Calculated Diplomatic Moves to Face Northern Wei

It was in the thirteenth year of King Jangsu's reign (425) that Koguryo made its first contact with Northern Wei. This was simply recorded in History of the Three Kingdoms that Koguryo had sent an envoy to Northen Wei, which is evidently too brief to learn the details. Supposedly, the dispatch of an envoy was intended to explore Northern Wei, the rising new power in northern China. Ten years later, in the twenty-third year of King Jangsu's reign (435), an envoy was sent to pay a tribute to Northern Wei. Reportedly, Northern Wei was glad to receive the tribute from Koguryo, because it was also well known in Northern Wei that Koguryo was the strongest power in the Liadong region. By paying a tribute to Northern Wei first, Koguryo recognized the status of Northern Wei in reality. Northern Wei sent an investiture envoy to invest King Jangsu as king. Northern Wei went through the trouble of sending an investiture envoy because the envoy was intended to spy on the situation of Koguryo. From this point on, Koguryo entered into official diplomatic relations with Northern Wei.

The reason why Koguryo directed its interest and sent another envoy to Northern Wei in ten years was Northern Yan bordering with Koguryo on the west. Northern Yan had been in a friendly relationship with Koguryo during the King Gwanggaeto era. Northern Yan was managing to fend off the attacks of Northern Wei, but with difficulty. At the time in the fifth century, Northern Wei was occupying North China, Northern Yan was occupying the Liaoxi and Hebei regions, and Koguryo was occupying the Liaodong region. Located between Northern Wei and Koguryo, Northern Yan served Koguryo as a buffer zone. If Northern Yan weakened or perished, Koguryo would have to face the Northern Wei force directly. Northern Wei at the time tried to gain control of the Liaoxi region. Liaoxi was a stronghold that enabled any force occupying this region to exert influence on neighboring forces. Liaoxi was also an important route for advancing into inland China.

It was only recently that Koguryo's capital had been relocated to Pyeongyng in the fifteenth year of King Jangsu's reign (427). Under the circumstances, King Jangsu felt threatened by Northern Wei attacking Northern Yan. It was against this backdrop that King Jangsu sent an envoy to pay a tribute to Northern Wei. King Jangsu must have struggled to figure out what kind of diplomatic attitude he should take in the international situation at the time to ensure Koguryo's safety.

Koguryo's fear became a reality when Northern Wei attacked Northern Yan in 436. Northern Wei sent envoys to Koguryo and other neighboring countries telling them not to support Northern Yan. However, King Jangsu didn't comply with this request, but sent two generals, Galo (葛盧) and Maenggwang (孟光), to Longcheng (龍城), the capital of Northern Yan. The army of Koguryo faced the army of Northern Wei, until it retreated with Feng Hong (馮弘), the king of Northern Yan, and his followers. In other words, even though Northern Wei overthrew Northern Yan in 436, the king of Northern Yan escaped alive. Emperor Taiwu of Northen Wei sent an envoy demanding the repatriation of Feng Hong, but Koguryo evaded the demand while presenting to the Emperor a letter that said, "Of course, we, together with the king of Yan, will follow Wei's instructions."

The Gwanggaeto Stele, erected by
King Jangsu in the second year of
his reign (411) to praise the
achievements of his father, King
Gwanggaeto, is located
in Jian in the Jilin Province of China.

Meanwhile, Feng Hong the king of Northern Yan complained that Koguryo was not treating him with the respect his original status deserved. In response, Koguryo separated Feng Hong from the group of exiles from Northern Yan, preventing their power from growing. In other words, Koguryo sent a diplomatic signal to Northern Wei that it would not assist the comeback of Feng Hong. The matter of Northern Yan then was very complicated. Feng Hong sent an envoy to Song (宋) of the South Dynasty requesting protection. Southern Song demanded that Koguryo should send back Feng Hong. Koguryo responded by ordering the generals to kill Feng Hong and about a dozen people in his family. In the process, the army of Koguryo clashed with the army of Song. Koguryo lost a general, but ultimately captured a commander of Song. It was then that Koguryo used its diplomatic abilities once again by sending back the captured commander of Song, leaving a possibility to establish ties with Song in the future. On its part, Song didn't let this incident develop any further, either.

Forging Strategic Friendly Relations with the North and South Dynastie

In the international relations surrounding Northern Yan in the 430s, Koguryo placed utmost importance on national security and implemented practical foreign policies accordingly. Koguryo's foreign policies had both hard and softs sides to ensure that war would not occur. King Jangsu tried to maintain a close relationship with Northern Yan and protect Feng Hong because he wanted to keep internal stability for Koguryo, which had recently relocated its capital to Pyeongyang. After the downfall of Northern Yan, Koguryo and Northern Wei were in tension as they bordered each other in Liaoxi, but resumed their diplomatic relations in twenty-three years in the fiftieth year of King Jangsu's reign (462). From then on, Koguryo sent envoys to Northern Wei regularly, almost every year.

Meanwhile, King Gaero of Baekje sent an envoy to Northern Wei in 472 asking them to attack Koguryo. However, Northern Wei had the Rourans (柔然) and Southern Song beyond its lines. Accordingly, Northern Wei refused Baekje's request, on the excuse that Koguryo was never late in paying tributes, and also saying that it had 'rebuked Koguryo.' This was the incident that prompted King Jangsu to pay a tribute to Northern Wei and Southern Song between 472 and 475. Once safety had been secured in the relations with Northern Wei in this way, King Jangsu attacked Baekje in September of 475, killing King Gaero and took the Han River basin.

널리As is widely known, King Jangsu effectively handled the diplomatic relations forged with the South Dynasty and the North Dynasty in connection with the international situation at the time. While he was focused on establishing diplomatic ties with the 'difficult neighbor' Northern Wei, he also forged diplomatic relations with Song or Qi (齊) of the South Dynasty. King Jangsu forged 'strategic friendly relations' with Northern Wei, Northern Yan, the Rourans, Southern Song, and Southern Qi. From the perspective of the history of diplomacy, King Jangsu was a brilliant figure who properly coped with the complex international situation of East Asia at the time and maximized the national interests.