The Yi Dynasty was founded by the Koryŏ general Yi Sŏng-gye, who first staged a nearly bloodless coup against King U, then forced the abdication of Kongyang, the last king of Koryŏ.

The end of the Koryŏ Dynasty Koryŏ Dynasty[Koryo Dynasty] (918-1392) was plagued by social disorder and foreign invasions. In the thirteenth century, the increasingly powerful Mongols, nomads from the north central Asian steppe, were destined to make a significant mark on Koryŏ’s history. The Mongols swooped down on China and defeated the Jurchen Jin (Chin; 1115-1234) and Southern Sung Dynasties (Song; 1127-1279). [kw]Establishment of the Yi Dynasty (July, 1392)
[kw]Yi Dynasty, Establishment of the (July, 1392)
Yi Dynasty
Korea;July, 1392: Establishment of the Yi Dynasty[3030]
Government and politics;July, 1392: Establishment of the Yi Dynasty[3030]
Kublai Khan
U, King
Yi Sŏng-gye
Chŏng To-chŏn

Koryŏ suffered more than a half dozen invasions by the Mongols from 1231 until it finally surrendered in 1259. Korea;Mongol invasions of Koryŏ was able to resist for as long as it did because the court moved to the island of Kanghwa Kanghwa , at the entrance of the Han River. Though but a short distance from the mainland shore, the court’s location was nevertheless a major factor, for the Mongols were not familiar with sea warfare. Rather than waging war on the island, the Mongols ravaged the peninsula instead. After Koryŏ’s surrender, Kublai Khan Kublai Khan invaded Japan twice (1274 and 1281) by way of Korea, forcing Koryŏ to contribute material and troops.

Although thirty years of war with the Mongols brought about the physical destruction of Koryŏ, after Koryŏ’s surrender, its court developed a unique relationship with that of the Mongols. In an attempt to bolster his power in court, Koryŏ king Wŏnjong Wŏnjong (r. 1260-1274) received Kublai Khan’s daughter as consort for his crown prince. Henceforth, several succeeding kings took Mongol princesses as their wives.

After marriage, the crown princes of Koryŏ would stay in the Mongols’s Yuan court under hostagelike conditions until it was time to ascend the throne. Although the Koryŏ kings received some protection from the Mongols, the authority of the kingship was severely weakened, and Koryŏ all but lost its independence. The Mongols involved themselves with Koryŏ’s internal affairs and made what the Koreans viewed as excessive demands for materials as well as for eunuchs and maids. Also, under the protection of the Yuan court, abuses of power and other official misconduct were rampant. This relationship lasted for more than a hundred years until the end of the Yuan Dynasty Yuan Dynasty (1279-1368).

In the 1350’, Yuan’s power waned, and the Mongols were driven back north by the rising Ming Dynasty Ming Dynasty (1368-1644). During this transitional period, a power vacuum emerged in the northeastern part of Korea and in Manchuria, which presented a window of opportunity for Koryŏ. King Kongmin Kongmin Wang (r. 1351-1374) seized the opportunity by retaking the northeastern territory of Hamkyŏng Province (1356). Yi Chach’un Yi Chach’un , the father of Yi Sŏng-gye Yi Sŏng-gye who would later found the Yi Dynasty, led the expedition. For his valor, the king rewarded Yi Chach’un and appointed him general for the region. Following in his father’s footsteps, Yi Sŏng-gye distinguished himself in many military campaigns.

Koryŏ’s border troubles not only involved China but Japan as well. Attacks by Japanese pirates were not new, but during the late Koryŏ period, especially beginning in 1350, their depredation amounted to a national crisis. Half-naked and armed with long swords, these marauders would land at any time and any place along the coastline of the peninsula, pillaging and burning coastal villages and carrying away their booty. According to historian Wanne J. Joe, during King U U, King ’s reign alone, 378 incursions took place. Here, too, Yi Chach’un, and later, Yi Sŏng-gye, played important roles in repelling the Japanese.

Yi Sŏng-gye distinguished himself in battles repulsing the Red Head Robbers Red Head Robbers , one of the Chinese groups from the north who were then ravaging the country, even occupying the capital, Songdo (Songak), in 1360. In 1370, Yi captured the Liaotung region of south Manchuria from the retreating Mongols, albeit for a short time, fulfilling Koryŏ’s long cherished desire to retake what had once been part of Koguryŏ, as Koryŏ claimed to be the legitimate heir to that kingdom. Only a few generations earlier, this upstart Yi family from Chŏlla Province had moved to the Hamkyŏng Province in search of better opportunities. Eventually, Yi Sŏng-gye Yi Song-gye became one of the most renowned generals of the era.

In February, 1388, the Ming Chinese threatened to retake the Hamkyŏng Province area by establishing a Ch’ollyŏng commandery and arguing that the area had earlier belonged to the Mongols and therefore must be a part of the Liaotung region, which was then under Ming control. Koryŏ’s supreme commander, general Ch’oe Yŏng, responded by mobilizing an army to attack the Liaotung peninsula once again. However, there was dissension within the ranks. General Yi Sŏng-gye, one of the two deputy commanders who were to direct the campaign under Ch’oe Yŏng, objected to the campaign, despite having successfully attacked the same region in the past. One of the main points of his objections was characteristically Confucian. He said, “It is wrong for a small country to attack a large one.”

General Yi set out reluctantly. However, in the middle of the campaign, defying King U’s order to march on to Liaotung, he turned his army around at Wihwa Island on May 22, 1388, crossed the Yalu River again, and marched back to the capital. He overthrew King U and exiled his superior, General Ch’oe Yŏng Ch’oe Yŏng , both of whom he later killed. The withdrawal from Wihwa signaled the beginning of the end of Koryŏ as Yi Sŏng-gye now controlled the military. Referring to the botched campaign of Manchuria, the historian Joe wrote, “The evil that defeated this heroic venture was the enemy within, as represented by Yi Sŏng-gye.” Yi Sŏng-gye adopted the old name of Chosŏn for his state, known as the Yi Chosŏn Dynasty Yi Dynasty . Two years later, he moved the capital from Kaesŏng (former Songdo) to Hanyang (present-day Seoul).

Although Koryŏ had been firmly Buddhist, Yi T’aejo (posthumous title) filled his government with followers of the Chinese philosopher Confucius, most notably Chŏng To-chŏn Chŏng To-chŏn , Yi’s deputy commander and a neo-Confucian scholar who later formulated many policies in the fields of government, law, and religion. Many decrees were issued that, over time, effectively made Confucianism Confucianism;Korea the dominant philosophy in the kingdom. One of the central tenets of Confucianism is the importance of the five cardinal relationships: ruler and subject, father and son, husband and wife, brother and brother, and friend and friend. The unconditional loyalty and respect that Confucianism prescribes within these relationships have long been characteristic of the Korean people.

Yi Sŏng-gye succeeded in ridding Koryŏ of many foreign invaders and was the forefather of a new line of monarchs that lasted more than five hundred years and had a lasting impact on Korean society. He established Seoul as the capital of the state. The rise of Confucianism greatly affected the way the Korean people view their relationship to their government and to each other. During the reign of Yi Sŏng-gye’s grandson King Sejong Sejong (r. 1418-1450), Korea enjoyed some of its most peaceful and prosperous years, including the invention of the Korean alphabet, hasngŭl, which because of its scientific logic and simplicity is so easy to learn that illiteracy in Korea is nearly nonexistent.

• Duncan, John B. The Origins of the Chosŏn Dynasty. Seattle: University of Washington Press, 2000. Deals with the question of the main cause of the dynastic change from Koryŏ to Yi.
• Hulbert, Homer B. Hulbert’s History of Korea. 2 vols. London: Routledge & Kegan Paul, 1962. Presents the most detailed account of Korean history from antiquity to 1904 in the style of annals. However, some of Hulbert’s accounts disagree with from more recent works.
• Joe, Wanne J. Traditional Korea: A Cultural History. Vol. 1 in A History of Korean Civilization. Seoul: Chung-ang University Press, 1972. Gives a comprehensive and well-balanced view of Korean history.
• Lee, Ki-baik. A New History of Korea. Translated by Edward W. Wagner. Cambridge, Mass.: Harvard University Press, 1984. A concise overview of Korean history. The “Dynastic Lineages” section is especially helpful.
• Rutt, Richard. James Scarth Gale and His History of the Korean People. 2d ed. Seoul: The Royal Asiatic Society, Korea Branch, 1983. Based on the history written by James Gale, a contemporary of historian Homer B. Hulbert. Gale and Hulbert were born a month apart and served together at the court of the emperor Kojong (r. 1864-1907) at the end of the Yi Dynasty.