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Blood and Water

How Chosŏn Korea Won Against Hideyoshi’s Japan, 1592-1598

Towards the end of the sixteenth century, feudal Japan, unified under its leader Toyotomi Hideyoshi, invaded Chosŏn Korea in 1592. The resulting Imjin War was a conflict on a uniquely monumental scale, entailing hundreds of thousands of combatants. It also marked a turning point in the geopolitical situation in East Asia. The massive force of Japanese ashigaru (foot soldiers) and their leading samurai cut down droves of unprepared Chosŏn soldiers, and occupied large swaths of the Korean peninsula. Despite this initial success, the Japanese war machine soon ground to a halt, with Ming China also joining the conflict to aid their Korean allies. Interrupted only by a short period of negotiation, the Imjin War ended after the Japanese withdrew their troops from Korea in 1598. While being ubiquitous in Korean history and pop culture, the 1592-1598 invasions remain virtually unknown in the English-speaking world, and subsequently often misunderstood. This essay will rectify common errors that are propagated about the conflict while providing a streamlined explanation for why and how Chosŏn Korea was able to achieve victory. The outcome of this bloody war can be understood through the core concepts of “food and governance,” with the area of logistics being the reason for Japan’s downfall (Hur, “The Politics of Food and Governance in the Imjin War”). The Koreans’ subsequent targeting of these weaknesses through guerilla warfare and naval superiority proved to be the saving grace for their small nation.

On the eve of the Imjin War, the Chosŏn government was put to the ultimate test. Open threats by Toyotomi Hideyoshi and overall hostility from the Japanese government had already led to Chosŏn being wary of a potential invasion. It was this pivotal moment where a capable leader would be expected to channel Korea’s resources into an effective defense in depth that could hold back the coming storm. King Sŏnjo proved woefully unfit for the task at hand. The Chosŏn government at the time was beset with extreme factionalism that the weak Sŏnjo could do little to rectify. The two main factions, known as the Easterners (Tongin) and the Westerners (Sŏin), bickered endlessly over the correct Neo-Confucian interpretations of the classical texts. Their rivalry hindered a streamlined policy of defense against the looming Japanese threat (Wagner 1-4). The resulting preparations for warfare were pitiful: the timorous Korean government’s construction of land fortifications was limited in scope and crudely built (Kim 18). There was no attempt to modernize the Korean army’s weapons; the adoption of muskets would only come about after the Japanese demonstrated its effectiveness in mass slaughter. The appointment of civil service officials to military positions was another unfortunate blunder, as it was commonly believed that knowledge of the Classics superseded tactical experience in the heat of battle (Wagner 18). The officers on the front-lines in turn proved to be more indicative of factional corruption than military competence. The collapse of the Chosŏn defense in the initial stages of the war would accentuate these glaring problems with Korea’s martial policy.

It would not be fair to put all of the blame on the reigning monarch in Chosŏn, as the Korean court was guilty of these sins as a whole. However, King Sŏnjo was the ultimate person of authority that could conceivably address these deep-rooted issues directly. His weak and debilitated performance as a leader indicated his inability to properly reconcile the national interest of Chosŏn with the squabbling Easterner and Westerner cliques. Indeed, when King Sŏnjo was forced to flee his capital after the Japanese laid waste to the southern half of the Korean peninsula in 1592, he composed a poem that encapsulated his failure to quell the factional strife that had ruined his small nation. 

 

As I wail to the moon over the border mountain, / The winds of Amnok [Yalu] wave pierce my bowels for aye; / O, my courtiers, do not say again / East or West from today!

(Ha 2)

 

By July of 1592, the Japanese had already abandoned any thought of invading China and were focused on consolidating their gains in Korea (Hitoshi 104-111). It was here when the first confrontation between the Ming and the Japanese occurred, with General Zu Chengxun leading a combined force of his Chinese troops from the Liaodong province and Chosŏn government troops against Japanese-occupied Pyongyang. The resulting battle was an unmitigated disaster, with Zu Chengxun barely escaping with his life and the sole Chinese presence in Korea being routed by Japanese forces (Turnbull 124-126).  Although Zu Chengxun bitterly blamed the Koreans for the defeat, there is ample reason to disregard this, as Chinese generals were notorious for assigning blame to the Koreans when they suffered defeat to avoid punishment. It would take more than four months for Ming forces to set foot again in Chosŏn to contend with the Japanese.

Nevertheless, King Sŏnjo saw the value in using Ming soldiers to bolster the Korean war effort. His own Korean government troops had been defeated time and time again by the more experienced and well-equipped Japanese. His continuous petitions to the Ming court for aid eventually bore fruit: additional Ming forces were sent to the Korean peninsula, partly because of Sŏnjo’s exaggeration of the Japanese threat against China (Yeon 523). However, by this point, the Japanese had already become bogged down and were experiencing difficulties inland because of a new kind of Korean resistance.

The Korean righteous armies, known as ǔibyŏng, were bands of guerilla fighters that took a very different approach to the war. In contrast to the Korean government troops that confronted the Japanese army directly, these civilian volunteers focused upon disrupting supply lines and ambushing foraging parties. These raids even extended into attacks on enemy strongholds within Chosŏn, with their efforts frustrating the overall offensive (Hawley 291-292).  Despite the fact that over half of the peninsula was under Japanese control, its occupation was tenuous due to the severe logistical difficulty of supplying more than a hundred thousand troops in a foreign land. These problems were exacerbated due to constant harassment by these Korean irregular troops, which Hideyoshi referred to as the ikki rebel forces (Hur, “The Politics of Food and Governance in the Imjin War”). By 1593, Hideyoshi’s goal of subjugating Chosŏn was already in doubt.

It was in January when the Ming Chinese arrived in significant numbers, with thirty thousand fresh Ming troops, headed by General Li Rusong. This massive force, assisted by a few Chosŏn regiments, sought a rematch at Pyongyang, where an intense battle ensued. Although the Ming–Korean forces penetrated the outer walls, the Japanese inflicted severe casualties on the allied forces and continued to put up a ferocious defense. General Li, shocked by the number of losses, ordered a withdrawal of his men and sent a secret message to the Japanese stating that he would let them evacuate without a fight (Gale 161). Later that night, the Japanese left Pyongyang, and the city was retaken.

It is important to note Ming China’s reluctance to commit to an all-out fight against the Japanese invaders. Time and time again, their conduct would demonstrate that they were more interested in pushing them back to the south than eliminating them entirely. This was partly because of China’s economic instability, poor weather, and supply issues of their own (Hawley 303-305). More importantly however, it was also recognized that the Japanese were already losing grasp on their conquered territory. Rather than needlessly waste Chinese lives, they hoped that the enemy could be induced to retreat through a show of force. The Koreans, of course, were deeply irritated by this, and constantly worried that the Chinese were not as dedicated as them to destroying the enemy.

Why then, were the Koreans so generous with their praise to Ming China in official documents? The answer is because of the underlying power structures that defined their diplomatic relationship. Chosŏn Korea was a tributary state to the Ming empire, and received safety and security in exchange for acknowledging the mighty Celestial Kingdom as the pinnacle of civilization. Appealing to China as an honorable and all-powerful empire was Korea’s ultimate political strategy during the late sixteenth century (Wang 246-247). To openly disparage their closest ally was thus not an option. Instead, King Sŏnjo and his fellow courtiers gritted their teeth and continued to cajole the Ming to be more aggressive in the fight against the Japanese barbarians. Although Ming involvement steadily increased from 1592 to 1598, its role in changing the tide of war was ultimately secondary. It was staunch Korean resistance, first and foremost, that was the most pivotal in damaging the logistical capabilities of the Japanese occupation.

The war was not only limited to land. In fact, the greatest military victories that Choson achieved was through its navy, particularly under the command of the famous admiral Yi Sun-sin. Despite the Japanese enjoying superiority in pitched land battles, the Korean navy proved to be much more effective at sea due to their modernized strategy of distanced combat. The development of advanced naval artillery allowed the Koreans to concentrate cannon fire on the enemy from afar, and stay relatively safe. The Japanese conception of naval warfare was considerably more medieval, and depended on close combat via boarding parties (Hawley 204-206). The Korean panoksŏn (board-roofed ships) and kŏbuksŏn (turtle ships) were the most advanced battleships of the East Asian naval sphere and greatly outclassed their Japanese counterparts.

Under Admiral Yi, the small Korean navy won a string of naval victories in 1592 against Japanese ships venturing into the Yellow Sea at Okpo, Sach’ŏn, and Tang’p’o, without the loss of a single vessel. It was then when Hideyoshi ordered his daimyos to pool their naval resources and completely eliminate the Korean navy for good. The momentous battle would take place at Hansan Island, where Yi found himself facing a numerically superior Japanese force of seventy-three warships, headed by the daimyo Wakizaka Yasaharu. The cunning Korean admiral rearranged his battle line into his famous crane-wing’s formation, which capitalized on the power of his naval artillery. Nearly all the Japanese ships were smashed to pieces, with Yasaharu’s fleet being completely decimated. Following the disaster, the horrified Hideyoshi ordered all naval operations to cease for good (Turnbull 55-78).

These outstanding victories by Yi occurred in tandem with the terrible losses that were taking place on land in 1592. It's important to emphasize that these were not merely flashy tactical victories that boosted Korean morale. Rather, they were a blow to the very core of the Japanese war effort. The initial invasion of the peninsula had certainly been tremendously successful, but after months of fighting, provisions began to dwindle. Keeping over a hundred thousand soldiers well fed and supplied proved an exceptionally difficult task, especially with the involvement of guerilla resistance movements inland. Korean naval dominance added yet another problem for the Japanese, as it prevented the resupply of their forces through the Yellow Sea. The Korean prime minister Yu Sŏngnyong recognized the value of this achievement, stating:

 

The Japanese had now taken Pyongyang, but they did not dare advance any farther without first receiving reinforcements via the Yellow Sea. Thanks to this one operation led by Yi Sun-Sin, such reinforcements would never arrive. By denying their navy entrance to the Yellow Sea, Commander Yi effectively cut off one arm of the Japanese advance … Indeed, it must have been an act of divine providence.

(Hawley 237)

 

Hideyoshi had not anticipated this, as he no doubt expected the easy vanquishing of the Chosŏn navy, just as he had done to their army in 1592. His soldiers would now face two critical threats to their logistics, without which an occupation would be impossible: the ǔibyŏng armies that harassed the inland supply routes, and Admiral Yi’s panoksŏns and kŏbuksŏns that thrashed supply ships coming into the Yellow Sea. Faced with these overwhelming problems, it is not surprising that the Japanese pursued efforts for negotiation by 1593.

King Sŏnjo on the other hand, achieved little. He failed to prepare the nation adequately for the brutal assault on his kingdom. He failed to unify his own court and fled the capital when the Japanese swarmed through his own country. His only accomplishments were his desperate calls for help, whether it was to Ming China, or to the Buddhist warrior monks that his own government had persecuted for centuries (Haboush 53–54). The war was not won by the Korean state, but rather the Korean people themselves. Far from becoming subservient to Hideyoshi like many of his other defeated foes, they resisted his conquest and fought back against the largest amphibious invasion in the history of the world at the time.

The enemy army did not melt away immediately. The Japanese, after all, were not willing to go quietly and wished to save face in the wake of their stalled offensive. By 1593, Hideyoshi was forced to reassess his goals. It was now certain beyond a doubt that Chosŏn could not be fully conquered. However, he hoped that Japan could still obtain some concessions from his initial gains. After intense deliberation and negotiation that lasted several years, he agreed to a settlement in 1596 with the Ming–Chosŏn coalition under the conditions that he would be granted a special royal title by the Ming. As a show of gratitude, Hideyoshi pulled the bulk of his force to a select few fortresses in the south (Hur, Works in English on the Imjin War 69). Despite King Sŏnjo and his court being loath to negotiate with the hated Japanese, especially when the enemy hadn’t even left the Chosŏn territory, Ming China dictated most of the diplomatic correspondence due to their higher status, and were eager for the war to come to a swift end. Their hopes would soon be dashed.

When the Ming envoys came to Osaka to grant Hideyoshi the official title of ‘King of Japan,’ all seemed to be going as planned. A ceremony of investiture was carried out, with him receiving lavish regalia and an official seal from the Ming emperor. In this way, the Ming hoped to grant him an ultimately meaningless title to appease Hideyoshi and end the war at the least cost to themselves (Xing 5030-5032). Following the ritual, a letter was sent ordering that he fully remove his troops from Chosŏn now that he was an official vassal of Ming China.

Hideyoshi was furious. He had understood that the Korean peninsula would not be his and had long since abandoned any idea of invading China. Through a long series of negotiations he had slowly whittled down his demands to something that barely resembled his original ambitions. By going through the process of investiture, he had hoped that the Ming would gracefully exit the conflict and allow him to continue to press the Koreans for concessions (Hwang and Matsuda 321-322). It now became clear that the Ming and the Koreans were not going to give him anything, with the supposed title being a complete sham. Hideyoshi immediately ordered a second invasion of the Korean peninsula. His main goals would be twofold: to enact vengeance against Chosŏn, and obtain the concessions he so desired to exit the conflict under the guise that he had won.

The Japanese returned in 1597 with the explicit understanding that Korea could not be conquered. Hideyoshi accordingly ordered his troops to focus upon controlling the southern provinces of Chosŏn rather than attempting to retake the capital. In order to stave off the logistical problems that had plagued the first invasion, he hoped that his forces could live off the land and secure food from the Korean population (Hawley 423-424). To do this, he would have to quell the guerilla resistance, an objective he pursued by ordering his soldiers to be even more brutal. Mass atrocities were carried out, including the slaughter of entire villages and the collection of Korean noses as proof of his daimyos’ contributions to the war effort (Hur, “Atrocity and Genocide”). Despite the devastation that the Japanese inflicted, Korean resistance continued, with the terror only fomenting more anger towards the invaders. The land campaign of 1597, in turn, was marked with particular savagery and violence.

Hideyoshi also demanded the destruction of the Korean navy, which had been so effective during the early invasions of 1592. This began with the carefully plotted sabotage of the capable Yi Sun-sin. Using a double agent, the Japanese damaged Yi’s reputation and used the chaos of Korean factional politics to turn the government against him (Hawley 409-417). He was imprisoned and tortured. The court replaced him with the incompetent Wŏn-Kyun, who proved grossly inadequate as a naval tactician. At the Battle of Ch’il’-ilch’ŏnnyang, almost the entire Korean navy was decimated, which took the lives of all the senior naval commanders including Wŏn-Kyun himself. King Sŏnjo and his court had no choice but to reappoint Yi Sun-sin to high command. In the subsequent Battle of Myŏngnyang, Admiral Yi used the remnants of his naval force, numbering only thirteen warships, to fight a last stand against one hundred thirty-three Japanese vessels. The Japanese suffered a humiliating defeat after being unable to break through the Korean battle line, and were consequently blocked from entering the Yellow Sea for the rest of the war (Hawley 455-463).

            What did the Ming think of the second invasion? For starters, they were astonished and outraged that Hideyoshi would break the truce. They immediately ordered a battalion of fresh troops under the command of General Yang Hao to Chosŏn to deal with the barbarian threat once and for all. The arrival of Ming reinforcements in even greater numbers forced the Japanese to retreat further south. In late December 1597, the entirety of the Ming force, coupled with a few Chosŏn divisions, advanced upon the stronghold of Ulsan (Swope 168-195). The defenders put up a desperate fight, using their musketeers and the cover of pouring rain to make a siege untenable. Even after wave after wave assaulted the walls, the Japanese managed to hold back the combined attack until Yang Hao gave up and lifted the siege.

Hideyoshi approved of his army’s performance. The punishment that he had inflicted upon Chosŏn, particularly in the Chŏlla and Ch’ungch’ong provinces, had upheld Japan’s military strength and honor. However, the obstinate Koreans still refused to give him concessions, whether it was one of their princes as a hostage, or even some loose gifts as a sign of their submission. Faced with his military position slowly becoming weaker and his own health failing him, Hideyoshi ordered an evacuation of his troops in 1598 (Hur, “The Politics of Food and Governance in the Imjin War”). He would die later that year in August. A poem he composed on his deathbed embodied the futility of the war he would never see end.

 

I am as / The dew which falls, The dew which disappears. / Even Osaka Castle / Is only a dream.

(Hawley 501)

 

Keeping in line with their behavior in 1593, the Chinese were not as willing as the Koreans to pursue the retreating Japanese. From the Ming’s perspective, the Japanese had given up the fight and were returning home. For the Koreans on the other hand, it was not enough that the Japanese were fleeing. They desired revenge, something that could feasibly be carried out by the one force that had proven to be consistently effective throughout the war: Admiral Yi’s navy.

Yi had not been idle following his victory at Myŏngnyang, with him increasing the size of his fleet to roughly a hundred during the later months of 1597 and even playing a supportive role at the Battle of Ulsan through naval bombardment.When the Japanese forces began to evacuate, he attacked their supporting navy with the reluctant aid of Chinese general Chen Lin at Noryang Strait. The combined fleet annihilated the enemy armada, though tragically, Admiral Yi was killed by a Japanese sniper (Haiying 165-203). The Battle of Noryang would be the last major battle of the Imjin War. The rest of the occupying force would limp back to Japan, never to return to Korea again.

In seven years of war, the Koreans had endured much hardship. The violence and chaos brought upon by the Japanese invasions of 1592 to 1598 wreaked havoc upon the small nation-state. And yet, they had survived. The Chosŏn dynasty under King Sŏnjo was kept intact, and his countrymen had successfully pushed back the enemy into the sea.

Japan, meanwhile, achieved nothing. Their conquest yielded little in terms of material wealth or political gains. Hideyoshi’s demand for concessions went unanswered by the Koreans, who refused to grant him even the most insignificant forms of tribute that he could use to justify the bloody conflict. The Imjin War weakened Hideyoshi’s regime, with his death only marking the beginning of the end. His son, Hideyori, would not live long. Following the return of Japanese troops to the mainland, a rival daimyo by the name of Tokugawa Ieyasu murdered Hideyori and established himself as the ruling shogun of Japan (Eisenstadt).

The outcome of the war is then clear: Korea, with the assistance of the Ming, successfully defended their kingdom against Japan, which was ultimately forced to withdraw. The logistical difficulties that Japan faced were compounded by local guerilla resistance on land and by the Korean navy at sea. These factors alone were able to stop the Japanese advance. The addition of the Ming forces accelerated the decline of the Japanese occupation and aided the Koreans in pushing the Japanese out of Chosŏn. Although Hideyoshi made the order to evacuate in 1598, the war had already become a lost cause far earlier. It was this fiasco that would earn the conflict’s name in Japan: the Dragon’s Head-Serpent’s Tail campaign, alluding to the conflict’s initial gains that ended in abject failure.

While only spanning seven years, this period captured the Korean consciousness and would be remembered as the first time that Japan had invaded its shores. It would not be the last. Over three hundred years later, in the nineteenth century, Imperial Japan made another attempt to control the Korean peninsula, culminating in Korea’s occupation as a Japanese colony from 1910 to 1945. Although this period is undeniably more prevalent in the minds of modern Koreans today, the 1592 to 1598 invasions are nevertheless an important episode in the tumultuous relationship between these two countries. It is apt then, that the Imjin War is becoming more well-known in English language circles, and it is the hope of the author that more people choose to engage with its history.

Metadata

Luna Choi, “Blood and Water,” UCLA Korean History and Culture Digital Museum, accessed June 13, 2024, https://koreanhistory.humspace.ucla.edu/items/show/94.