Korea: The Great Invasions, 1592–1636

The Japanese landing on Busan


1590      Dispatch of Korean diplomatic mission to Japan to gage Japanese leader’s intentions

1592      Japanese invasion of Korea; Chinese entrance into the war in Korea’s defense

1597      Second Japanese invasion

1598      Retreat of the Japanese; end of the war

1601      Establishment of the Tokugawa Shogunate in Japan

1623      Overthrow of the Korean king by pro-Chinese monarch

1627      First Manchu invasion of Korea

1636      Second Manchu invasion

1644      Manchu conquest of China


Though little known outside of Asia, the East Asian war of 1592–8 stands as one of the major events in world history. For the first time since the aborted Mongol invasions of Japan in the thirteenth century, the major civilizations of East Asia became embroiled in a single conflict, with consequences that would far exceed any other in this region’s history until the late nineteenth century, perhaps indeed until the Pacific War of 1937–45. Begun through the Japanese invasion of Korea in 1592 in a bid to conquer Ming dynasty China itself, this war, fought exclusively in Korea, brought together all three countries in a fierce seven-year period of conflict. The destruction was enormous—to the Chinese who sent huge armies in Korea’s defense, and even to the Japanese. In Korea, the scale of the devastation can scarcely be imagined: hundreds of thousands killed, millions injured or uprooted, and a poisoning of relations with Japan that would never disappear.

That Korea survived this onslaught is itself a miracle. The most common Korean perspective relates that the country was rescued by its greatest military hero, Admiral Yi Sunsin, who helped staunch the destruction in 1592 by leading the Korean naval forces to key victories over their Japanese counterparts. Not long after his heroics, however, Admiral Yi found himself in a Seoul jail, awaiting judgment on charges of treason and incompetence. When, after four years of stalemate, peace talks collapsed and the Japanese sent another invasion force in 1597, Admiral Yi was freed and ordered back to the Korean coast to coordinate his command with the Chinese allies. This helped bring the conflict to an end in 1598. But the significance of this conflagration, albeit different in each country, would extend both geographically and temporally thereafter. It may have even paved the way a few years later for the rise of the Manchus, who also launched destructive invasions of Korea. For the Koreans, these wars exposed grave problems in the Chosn polity, but they eventually provided also an opportunity for sharpening their national identity and reassessing their civilizational standing in the northeast Asian region.


Although some Korean officials had suspected trouble brewing in Japan and even anticipated a conflict, the utter scale and catastrophic force of the Japanese assault in the spring of 1592 came as a shock: a landing force of hundreds of ships and tens of thousands of soldiers. The county officials of Tongnae, now part of the city of Pusan in the southeastern corner of the peninsula, managed to send messengers immediately on horseback to Seoul before the siege overwhelmed the Tongnae fortress. But the samurai soldiers, taking two invasion routes northward, tore through the country so quickly that within two weeks they were at the gates of the capital. After much hand-wringing with every report of the collapse of the country’s defenses, the Korean monarch, King Snjo, took the advice of his ministers urging him to abandon Seoul and flee northward. Along his path of evacuation, common Koreans, who enjoyed no such option, pleaded with him not to forsake his duties of protecting the capital, but clearly any attempt to withstand the barrage would have proved suicidal.

With the failure of its land defenses, the Korean court had to turn to its formidable navy, sending the two naval commanders for the southernmost provinces, Wn Kyun and Yi Sunsin, to engage the Japanese within a few days of the invasion. Admiral Yi Sunsin, in particular, enjoyed tremendous successes in these battles, destroying much of the Japanese fleet and thereby managing successfully to cut off Japanese supply lines along the coast. He is credited in particular with skillful deployment of smaller, highly maneuverable attack ships, including the famed “turtle boats” that were protected by a spiked armored shell. These breakthroughs proved sufficient to hold off the invaders until the Ming dynasty forces, sent by the Chinese emperor at the request of the Korean monarch, arrived to halt the Japanese advance in the decisive Battle of Pyongyang. The combined Korean–Chinese army pushed the invaders gradually southward, and as the Japanese retreated to fortresses along the southern end of the peninsula, negotiations began for a peace settlement.

Meanwhile, in spite of the recognition of his heroics accorded him by the court, Admiral Yi found himself embroiled in the factional struggles among high officials over responsibility for the stunning failure to prepare for, then counter, the invasion. Factionalism, a form of party politics, had evolved from the early-Chosn ideological conflicts among the throne and high officials to a system, ironically institutionalized in King Snjo’s reign, of hereditary political affiliation. Perspectives on Chosn dynasty factionalism have varied widely among historians, while the Japanese who colonized Korea in the early twentieth century cited factionalism as another example of the debilitating Korean political system.

Regardless of its ultimate significance in explaining Chosn dynasty politics as a whole, factionalism did play a central role in this period of major invasions from 1592 to 1637, as partisan disputes became entangled in formulating the court’s responses. One key example of this phenomenon came in the two years preceding the Japanese attack, when the Korean monarch sent a diplomatic mission to Japan to gage the intent of Toyotomi Hideyoshi, the Japanese leader who would later launch the invasions. The embassy’s report to King Snjo showed a division among its top two officials, members of rival factions. In implementing a response, one official’s warnings of an imminent Japanese invasion lost out to the reassurances of peace by the second official, whose faction enjoyed the upper hand in court. The court’s fateful decision not to mobilize the country in preparation for war proved disastrous. And, once again, partisan politics inserted itself into the government’s handling of crisis amidst the Japanese war, as Admiral Wn Kyun, who, in contrast to Yi Sunsin, had largely failed in his efforts to defeat the enemy at sea, blamed Yi for not carrying out orders to support him. As a stalemate in the war ensued, Wn’s factional ties to those in power in Seoul produced the amazing scene of Admiral Yi’s becoming incarcerated for insubordination and incompetence, and indeed of even being sentenced to death. The scramble to save his life by a few top officials was enough to prolong the stay of execution until the second Japanese invasion of 1597, which highlighted the folly of locking up Admiral Yi. Freed from prison and reinstated to his command, he immediately turned his attention to the southern coast. Alas, his leadership appears to have been critical to the conclusion of the war in 1598, as the joint Ming-Chosn forces, buoyed by news that Hideyoshi had died, chased the remaining Japanese soldiers off the peninsula—though not before a stray bullet killed Admiral Yi.


Admiral Yi’s death in a blaze of glory has served as the integral conclusion to the great narrative of heroism centered on this figure, whose feats of bravery and skill in the face of impossible odds are commonly recounted by Korean schoolchildren. By all viable historical accounts, Yi Sunsin was indeed an accomplished soldier, gifted strategist, and charismatic commander. From a prominent aristocratic family that had produced mostly civilian officials, he chose another path in his youth and, after passing the military examination with honors, soon ascended the ranks of the military officialdom. As naval commander of Chlla province, he stood as one of the few officials who foresaw the danger from Japan, and his preparations appear to have served him well once he engaged in battle, as chronicled in his diary-like official reports to the court. These sources, as well as other eyewitness accounts and government records, all point to Yi’s great deeds. But perhaps the source that contributed most to the mythologizing of Yi Sunsin as Korea’s greatest war hero was the Book of Corrections (Chingbirok), written by Yi’s staunchest supporter in the upper echelons of government officialdom, Yu Sngnyong. Yu had acted as one of Yi’s early patrons before the outbreak of war, and the Book of Corrections, in reference to the lessons that must be learned from the country’s failures in the Japanese invasion, likened Yi to a great spiritual force who almost single-handedly saved Korea. And Yi’s stoic righteousness in the face of factional injustice only heightened the impression of his purity.

In the modern era, another source of heroism has gained prominence in the conventional perspective on the Japanese war: the “Righteous Army” guerilla bands mobilized throughout the country to attack the invaders and obstruct the Japanese lines of communication and supplies. In the North Korean account of this war, for example, it is the Righteous Armies, representing the mass of the common, downtrodden people, who came to the rescue when the upper classes, including the monarchy, utterly failed to protect the nation. Such a populist perspective has become more accepted in South Korea as well, but, as scholars have pointed out, these bands, for all their effectiveness, appear to have been led by local aristocrats and thus replicated the hierarchies of society at large. To what extent these militias played a decisive role in the war’s outcome remains a point of contention. But regardless of the precise impact of these guerilla units, it seems fitting—given who suffered the brunt of the Japanese invasions—that they would be featured prominently in the national memory of the war. Indeed, their deeds lingered in the popular imagination thereafter, as seen in the reprisal of the “Righteous Army” moniker for ragtag militias that formed in the early twentieth century to resist, once again, the Japanese. In this sense, the prominence of the Righteous Armies in the narratives of national struggle reflects the intensification of Korean identity in opposition to Japan.

There remains, however, one final major factor in the war’s outcome that, in Korea at least, has not been readily highlighted: the Chinese. North Korean accounts understandably do not even mention the Ming dynasty’s assistance, for this would run counter to their hyper-nationalist narrative of Korean history. Even in South Korea, conventional perspectives on the war give little credit to the Chinese assistance. As for Yu’s Book of Corrections from the early seventeenth century, it paints the Chinese in mostly a negative light, focusing on their abusive behavior, their commanders’ neglect of Korean concerns in the negotiations with the Japanese, and their battlefield failures. Other recent scholarship, however, has questioned this longstanding impression and suggests that the Chinese forces played not only a key role in the allied victory over Japan, but indeed an indispensable one.


The significance of the Chinese contribution highlights the fact that, notwithstanding Korea’s suffering, this war’s impact spread far beyond the peninsula and may have been the most widely encompassing East Asian regional event until the modern era. Indeed the consequences extended even to an area originally untouched by the invasion, Manchuria. While there remains historical debate over the precise connections between the Japanese invasions and the conquest of Korea and China by the Manchus three decades later, the destructive force throughout East Asia could only have had a staggering, profound effect on the region.

Often overlooked when considering the fallout from the Japanese invasions of Korea is the pronounced impact on Japan itself, much of which, ultimately, was in fact beneficial. The lessons learned from the failure of Hideyoshi’s grand scheme, not to mention the expenditures of resources and lives, cast a long shadow over Japan’s subsequent history. Aside from megalomaniacal delusion, Hideyoshi’s primary reason for launching the invasion was to provide an outlet for the energies of his warrior retainers, who had proved instrumental in his completing the project of politically reunifying Japan after centuries of fragmentation. After his death, Japanese leaders would not again venture beyond their borders for over 200 years. In fact, the leader who emerged as Hideyoshi’s successor, Tokugawa Ieyasu, instituted a peaceful, stable, and in many ways a thriving dynastic rule based partly on the policy of “closure” to the outside world until the middle of the nineteenth century. The salutary effects of the Hideyoshi misadventure would extend to unforeseen realms as well: the many Korean artisans—artists, potters, smiths, ship builders, and others—taken as war captives back to Japan appear to have made a lasting contribution to the development of Japanese culture and technology.

As for China, the dedication of massive resources to the war against Japan—an act, admittedly, that was not devoid of self-interest, since Korea served as a buffer against the Japanese—could not have helped the Ming dynasty’s increasingly fragile grip on rule. After more than two centuries, the Ming government, having concentrated its energies on internal stability through limited foreign adventures, found itself having to beat back not only the Japanese, but also Chinese rebels and ultimately yet another “barbarian” group to its immediate northeast. The Manchus, descendants of tribesmen who had periodically organized themselves into a formidable military force throughout East Asian history, had suddenly done so again while the rest of the region was preoccupied with recovery from the Japanese invasion. By the 1620s, the Manchus, following the familiar pattern of the Northmen of East Asia in previous eras, appeared on the verge of striking Korea on their way to the big prize of China itself. The brooding specter of this invasion instigated a major factional struggle in Korea over how to respond, and eventually the king, who favored a policy of accommodation with this new power, was overthrown by Chosn’s high officials in favor of a more explicitly pro-Ming monarch. This soon brought forth the first of two devastating Manchu invasions of Korea in 1627, to be followed by the finishing blow in 1636, when the Korean monarch surrendered in ritualized humiliation to the Manchu emperor just outside of Seoul. This paved the way for the Manchus’ march into Beijing in 1644 and their takeover of China.

Despite succumbing themselves to the irrepressible Manchu force just a few years earlier, the Koreans were completely shocked by the Ming dynasty’s fall, which constituted, from the Korean perspective, an event on the level of a cosmic shift. For all the diplomatic subordination that the Koreans endured thereafter, the legitimacy of the ensuing Qing dynasty of the Manchus was never accepted by most Korean elites, who harbored a deeply ethnicized scorn for these “barbarians.” Indeed for well over a century Koreans openly retained fantasies of engaging in a “northern campaign” to overthrow the Qing. Koreans, now deprived of their long-held assumptions about civilizational order, were forced to reconsider their larger standing Under Heaven. A belief hardened among Korean elites that, with the fall of the Ming, only Chosn remained as a bastion of (Confucian) civilization. This accompanied the equally fascinating emergence of a more widespread sense of national consciousness among lower groups of people, as seen in the expressions of popular culture from the seventeenth century onwards. Indeed, the rallying cry of Yi Sunsin, Righteous Army leaders, and others around the common cause of national survival during the Japanese and, later, Manchu invasions laid the foundation for fortifying the idea of Koreanness itself.