Japan Invades Korea Summary

  • Last updated on November 11, 2022

In 1592, the Japanese warlord Toyotomi Hideyoshi ordered the invasion of Korea. His troops wreaked havoc on the country and were driven back only with the help of Chinese forces. The Japanese did not leave Korea until after Hideyoshi died in 1598.

Summary of Event

On the morning of May 23, 1592, the vanguard of a Japanese invasion force of more than 150,000 men landed on the southern coast of Korea. The invasion had been ordered by Toyotomi Hideyoshi, the military leader who was the de facto ruler of Japan. Having unified Japan on the battlefield, he believed he could conquer the rest of the world, starting with China. Moreover, launching a military campaign abroad afforded him a good opportunity to send his vassals, the daimyo (feudal barons or warlords) he had subjected, out of the way. Daimyos Although they had pledged loyalty, they still commanded strong armies; sending them on a foreign campaign would strain their resources and prevent them from challenging his authority. He issued an ultimatum to the Korean king, Sŏnjo, to grant passage to the Japanese for their invasion of China, and when this ultimatum was rejected, he ordered the invasion of Korea. Hideyoshi himself never left Japan; instead, he sent an army composed of his liege barons, each heading his own division. Korea, Japanese invasion of Japan;invasion of Korea Toyotomi Hideyoshi Katō Kiyomasa Konishi Yukinaga Sŏnjo Yi Sun-sin Toyotomi Hideyoshi Yi Sun-sin Konishi Yukinaga Katō Kiyomasa Sŏnjo Tokugawa Ieyasu Sŏnjo

Although the Koreans had been warned of the invasions, they were caught completely off guard. Severe factional fighting among the Confucian literati who ran the government and staffed the bureaucracy meant that a planned upgrading of the garrisons and the army had not taken place. After the Japanese had landed near Pusan and taken its fortresses, they met with very little resistance on their march to the capital, Seoul. The Japanese troops were battle-hardened through their experience in the wars of unification, and they possessed superior tactics, arms, and discipline. Moreover, they were equipped with firearms, introduced to Japan by the Portuguese in 1542. The Korean commanders and troops sent out to meet this invasion force simply were not up to the task and either were annihilated or ran away. As a result, in barely three weeks the Japanese reached Seoul, which fell without any resistance; Sŏnjo had fled with his court and ministers a few days earlier.

Not everything went well for the Japanese, however. After the initial walkover, resistance soon sprang up in the south, harassing the rear guard. At sea, the Koreans soon established supremacy thanks to the leadership of admiral Yi Sun-sin. His “turtle ships” caused the enemy all kinds of trouble: The decks of these flat-bottomed ships were completely covered in spikes hidden by straw, making them almost impossible to enter. They were effective both because of their firepower and because they could ram enemy vessels. Yi Sun-sin also used his knowledge of the many islands, inlets, and tidal systems to track down and destroy enemy vessels, thereby cutting off the main supply routes of the Japanese.

After regrouping in Seoul, the Japanese pushed farther north. A short distance beyond Seoul they split into two groups, one led by Konishi Yukinaga, pushing for Pyongyang, which fell on July 23, and one led by Katō Kiyomasa, which ventured into the northeast provinces. While Katō subjugated the northeast, imposing Japanese taxation and registration systems on the population, Konishi did not venture farther than Pyongyang. The fleeing Korean court, which had gone as far as the Yalu River, had appealed to the Chinese Ming Ming Dynasty (1368-1644);Korea and Dynasty, the suzerain state of Chŏson Korea, to intervene. After Chinese envoys had ascertained the gravity of the situation, a force of about three thousand soldiers was dispatched. The first Chinese soldiers crossed the Yalu on the same day that Pyongyang was taken. When this initial contingent proved too small to trouble the Pyongyang garrison, the Chinese initiated negotiations to bid for time until a larger force arrived. This larger force drove Konishi out of Pyongyang on February 8, 1593, forcing all the Japanese to retreat to Seoul. After a few months, Hideyoshi’s armies reached a truce with the Chinese emissary, evacuated Seoul, and dug in around Pusan in the southeast of the peninsula.

This marked the end of the first phase of the war. The Ming, as Korea’s suzerain, took it on themselves to negotiate with Hideyoshi and obtain full withdrawal; the Koreans were left out of these negotiations. Unfortunately, there was very little common ground in the worldviews of Hideyoshi and the Ming court. Hideyoshi demanded a treaty on an equal basis, to be sealed by a marriage between a daughter of the Chinese emperor and the Japanese emperor, and also expected to get the southern part of Korea. For the Chinese, the only possible form of foreign diplomacy was the submission of a “barbarian” foreign country to the Ming emperor, to be formalized by tribute missions from Japan and the investiture of Hideyoshi as king of Japan by the Chinese emperor. Konishi, as Hideyoshi’s main representative, knew that his master’s terms could never be met and did not relay the demands to the Ming court. After considerable subterfuge on the part of Konishi and his Chinese counterparts, a Chinese mission of investiture was finally sent to Japan in late 1596. Only after the ceremony of investiture was over did Hideyoshi learn that he had been misled and that none of his demands had been met. He flew into a rage and ordered the immediate resumption of the war.

This second phase of the war was fought mainly in the southern half of the country. The Japanese fell back on a few forts they had built in the southeast and successfully repelled the combined Chinese-Korean armies that tried to dislodge them. The Japanese commanders had had enough, however, and it was only Hideyoshi’s will that kept them in Korea. When news that Hideyoshi had died on September 18, 1598, finally reached them, they started to organize the retreat back to Japan. Fighting continued until the very last Japanese left the peninsula on Christmas, 1598. For the Koreans, the war ended only when the Chinese emperor officially proclaimed its end in the spring of 1599, at the same time absolving King Sŏnjo of any culpability in the invasions.


Hideyoshi’s invasions inflicted a terrible toll on the Korean people. It is impossible to estimate the exact loss of lives, but certainly it amounted to tens of thousands, as the grisly reports of severed noses sent back to Japan as proof of military success attest. Whole swaths of the countryside had been laid to waste, giving rise to famine and disease. The capital had been razed, and innumerable cultural treasures were destroyed or shipped back to Japan. Yet although it took decades for Korea to repair the damage, ironically the effect of the wars was arguably greater on China and Japan.

For Ming China, the economic burden of the Korean campaigns was one of the contributing factors to its decline and finally its demise in 1644. For Hideyoshi, too, the failure of his grandiose conquest undoubtedly weakened his leadership and interfered with his plans to secure a stable succession of leadership. Instead, power shifted to Tokugawa Ieyasu, who founded the Tokugawa shogunate when he became shogun in 1603.

King Sŏnjo, on the other hand, continued to reign until 1608 and secured the survival of the Chŏson Dynasty Chŏson Dynasty[Choson Dynasty] , which lasted until 1910. He even oversaw the resumption of normal diplomatic relations with Japan, formalized in a treaty the year after he died. Also, through these wars Korea achieved an important cultural impact on Japan. The artisans forcibly taken back to Japan contributed greatly to the development of Japanese crafts, especially pottery, while looted Neo-Confucian books and even some abducted scholars may have had an impact on the development of Neo-Confucianism in Tokugawa Japan.

Further Reading
  • citation-type="booksimple"

    xlink:type="simple">Elisonas, Jurgis. “War and Peace: The Background of Japanese Aggression in Korea.” In Early Modern Japan. Vol. 4 in Cambridge History of Japan, edited by John W. Hall. Cambridge, England: Cambridge University Press, 1991. Still the best overview of the development of the invasions and the political context.
  • citation-type="booksimple"

    xlink:type="simple">Ledyard, Gari. “Confucianism and War: The Korean Security Crisis of 1598.” The Journal of Korean Studies 6 (1988-1989): 81-119. Though this study deals only with the last phase of the war, it is important for treating the ideological dimension of the Korea-China partnership.
  • citation-type="booksimple"

    xlink:type="simple">Park, Yune-hee. Admiral Yi Sun-sin and His Turtleboat Armada. Seoul: Sinsaeng, 1973. Though dated, still the only English-language study of Yi Sun-sin’s exploits.
  • citation-type="booksimple"

    xlink:type="simple">Yi Sun-sin. Nanjung ilgi: War Diary of Admiral Yi Sun-sin. Translated by Ha Tae-hung. Seoul: Yonsei University Press, 1977. Yi Sun-sin’s war diaries are among the most important sources for the naval campaigns.
  • citation-type="booksimple"

    xlink:type="simple">Yi Sun-sin. Imjin changch’o: Admiral Yi Sun-sin’s Memorials to Court. Seoul: Yonsei University Press, 1981. Supplements his diaries, parts of which are missing.
  • citation-type="booksimple"

    xlink:type="simple">Yu Song-nyong. The Book of Corrections: Reflections on the National Crisis During the Japanese Invasions of Korea, 1592-1598. Translated by Choi Byonghyon. Berkeley: Institute of East Asian Studies, 2002. An attempt by King Sŏnjo’s prime minister to come to terms with the war’s causes and effects.

1457-1480’s: Spread of Jōdo Shinshū Buddhism

1467-1477: Ōnin War

1477-1600: Japan’s “Age of the Country at War”

Mar. 5, 1488: Composition of the Renga Masterpiece Minase sangin hyakuin

Beginning 1513: Kanō School Flourishes

1532-1536: Temmon Hokke Rebellion

1549-1552: Father Xavier Introduces Christianity to Japan

1550’s-1567: Japanese Pirates Pillage the Chinese Coast

1550-1593: Japanese Wars of Unification

Sept., 1553: First Battle of Kawanakajima

June 12, 1560: Battle of Okehazama

1568: Oda Nobunaga Seizes Kyōto

1587: Toyotomi Hideyoshi Hosts a Ten-Day Tea Ceremony

1590: Odawara Campaign

1594-1595: Taikō Kenchi Survey

Oct., 1596-Feb., 1597: San Felipe Incident

Oct. 21, 1600: Battle of Sekigahara

Categories: History