The Imjin War: Japan's Sixteenth-Century Invasion of Korea and Attempt to Conquer China

by Samuel Hawley

  Such was the case with the Mongol invasion of China beginning in the early 1200s and the subsequent rise of the Yuan dynasty (1271–1368). Between 1231 and 1258 the successors of Genghis Khan sent their mounted hordes six times against Korea, then under the Koryo dynasty, and eventually forced it to turn away from the declining Song dynasty and enter into a much more servile relationship with themselves. They then set their sights on Japan. The Koreans were required to build and man three hundred ships for the Mongols’ first, unsuccessful, invasion attempt of 1274. For the second invasion in 1281 the Koreans were compelled to contribute nine hundred ships of double the capacity, and fifteen thousand men. But this too failed. As the gargantuan Mongol-Korean armada approached the Japanese coast, a typhoon blew in from the west, grinding vessel against vessel until the roiling sea was a mass of wreckage and floating bodies. For the Japanese it was a miracle, a heaven-sent intervention they would remember as the kamikaze, the divine wind. For the Mongols, it was the beginning of the end of their dream of world conquest.

  After the failure of the invasion of Japan, the Mongol empire, and with it the recently established Yuan dynasty, began a slow and inexorable decline. The Yuan nevertheless maintained a tight grip on Korea for the next several decades. They exacted heavy tribute payments, exercised direct dominion over Korean territory, interfered in Korean politics, and in general conducted themselves in ways that ran counter to what Korea expected from the “Flowery Land.” When the Yuan dynasty began to crumble in the 1350s, therefore, the Koreans cut off tribute relations, ceased using the Yuan calendar, stopped wearing Yuan court dress and hairstyles, and moved to reclaim formerly Yuan-dominated territory, for in the words of one Korean commentator, “Heaven dislikes the virtue of the barbarians.” The new Ming dynasty, officially inaugurated in 1368, was then hailed as coming “from mid-heaven, in communication with sages and spirits of the past.”[66] The Koreans readily entered into a tributary relationship with it, hopeful of a return to the sort of autonomy their kingdom had enjoyed during the enlightened Song dynasty that had preceded the Yuan.

  Ming–Korean relations got off to a rocky start. The newly enthroned Hongwu emperor, anxious to establish his dynasty on a secure footing and consequently distrustful of all around, harbored suspicions about the Koreans throughout his thirty-year reign. Did they secretly remain loyal to the Mongols? Were they forging anti-Ming alliances with the Jurchen tribes of the east? These fears were not entirely unfounded. While it had no alliance with the Jurchen—Korea wanted only to drive them out of the northern territory they had seized during the declining years of Mongol power—there was indeed a significant pro-Yuan faction in Korea made up of those who had prospered under Mongol rule. Political affairs in Koryo, moreover, had become rather complicated by this point, for with the succession of the eleven-year-old King U in 1375, real power in Korea fell to the military men behind the throne, men whose loyalties the Ming court had no way of knowing. All this uncertainty placed a good deal of strain on relations between Ming China and Koryo Korea. Korean envoys were not always welcomed by the imperial court; some were even turned away at the border. The Chinese even went so far as to establish a garrison in northern Korea in 1388 on the grounds that the Koreans were failing to keep the Jurchen under control, an unpardonable breach of conduct in the eyes of many in the Koryo court.

  It was this border incursion that proved the flash point that would bring the already weakened Koryo dynasty to an end. The power behind the throne, General Choe Yong, angrily ordered the Korean army north to rout the Chinese garrison and send it back across the Yalu River. The general heading this army, a fifth-generation officer and fellow power behind the throne named Yi Song-gye, opposed this anti-Ming expedition and revolted. Turning his forces back against the Koryo capital of Kaesong, he ousted General Choe and King U and seized control. Yi ruled the country for the next four years through a series of puppet kings, then ascended the throne himself in 1392 and established a new dynasty, with a new capital in Hanyang, later known as Seoul.

  The first concern of Yi Song-gye, known to posterity as King Taejo, was to gain legitimacy for his dynasty. For this he turned to China. He dispatched an envoy to the Chinese capital to proclaim his succession and to swear loyalty to the Ming emperor. He solicited the emperor’s advice before selecting the ancient name of Choson, “morning calm,” for his new dynasty, a reference to the kingdom that had existed on the peninsula at the dawn of recorded history. He also began sending tribute missions west as evidence of his respect for the Celestial Empire and of his desire to resume sadae (serving the great) relations. Finally, in 1403, Choson Korea received formal investiture from the Hongwu emperor’s successor, and with that, friendly relations between the two nations were restored. Korea once again acknowledged China as the center of the universe, and China in turn acknowledged its loyal and civilized vassal as “different from all other states.”[67] As the relationship matured, Korea would send three or four embassies to China each year, while the Chinese reciprocated with an annual average of less than one.[68]

  While Korea cultivated its sadae relationship with China into the fifteenth century, toward other countries it pursued a policy of kyorin, “neighborly relations.” This was an outgrowth of the longstanding Chinese policy of wai i chi mi, which originally meant “to control and restrain wild horses and cows.”[69] To both the Chinese and the Koreans, barbarian peoples, like wild animals, did not respond best to brute force. They needed to be eased into the Chinese-centered universe through appeasement and conciliation, where they might then be tamed through exposure to civilizing influences. For the Koreans this approach was also highly expedient during the early years of the Choson dynasty. Until the dynasty was firmly established and its armed forces built up to some semblance of strength, King Taejo and his immediate successors had little choice but to buy peace with appeasement.

  There were two neighboring groups that put Korea’s kyorin policy to the test during the early years of the Choson dynasty: the Jurchen to the north and the wako pirates to the south. The Jurchen were a tribal people from Manchuria who had taken the opportunity of declining Mongol power to push their way down into the northern reaches of the Korea. They relied on Korean grain and cloth and tools for their existence and were equally prepared to obtain them through raids or through trade, whichever proved most convenient. During much of the latter Koryo dynasty the Koreans had attempted to drive these people back into Manchuria, mostly with little success. King Taejo chose a different course. He would not risk weakening his own recently established dynasty by continuing to fight them. He opted instead for appeasement. Since the Jurchen needed Korean food and goods to survive, he set up frontier markets and allowed them to trade for them peacefully. Jurchen who had settled in northern Korea were not driven out. A line a garrison forts was instead established along the Yalu and Tumen Rivers, fixing Korea’s northern boundaries as they remain to this day, and the Jurchen south of this border were accepted and naturalized as citizens of Choson and were in time integrated into Korean society. Jurchen leaders, meanwhile, were bought off with court rank and government positions. They were invited to Seoul to pay their respects to the king and engage in civilizing tributary relations, and not incidentally to profit from the de facto trade that such tribute missions entailed. They were, in short, given a stake in maintaining Korea’s security, in return for which they used their influence to keep their people peaceful and under control.

  King Taejo’s policy of appeasement toward the Jurchen was largely successful. It secured Choson’s northern border and bought his dynasty the peace it needed to gain legitimacy and establish itself. The Jurchen never entirely gave up their raiding ways, however, and would eventually reemerge as a significant annoyance in the latter half of the sixteenth century.

  The wako pirates—waegu to the Koreans—were a much bigger problem. They arose from the Matsuura region of Kyushu and the offshore islands of Tsushima, Iki, and Goto, areas of marginal farmland and li
mited options. As a Korean envoy to these regions would later observe, “[T]he people’s dwellings [here] are miserable; land is tight and, moreover, utterly barren, so that they do not pursue agriculture and can scarcely escape starvation; thus they engage in banditry, being of a wicked and violent cast.”[70] The influence of these Japanese brigands eventually spread all along Kyushu’s northern coasts and east to the Inland Sea. Then, in 1222, they turned their attention to Korea. From hidden lairs on Tsushima, less than thirty nautical miles off the Korean coast, they enjoyed several years of unopposed pillaging, until the Mongol invasion rendered the peninsula a more dangerous and thus less attractive target. A second surge in wako activity, this time not just in Korea but all along the Chinese coast and involving an increasing number of Chinese renegades, occurred with the decline of the Yuan and Koryo dynasties in the late fourteenth century. The Koreans were particularly hard-pressed this time to deal with the raiders, for they had not yet rebuilt their navy following the departure of the Mongols, who had forbidden them from possessing fighting ships. The wako pirates consequently owned the seas between Korea and Japan. Their dominance was so complete that they were able to seize entire fleets of cargo ships carrying tax rice from Korea’s southern agricultural provinces to the capital of Kaesong in the north. When the Koreans began transporting grain overland, the wako simply moved inland to loot government granaries. Except for one setback in 1350, when Korean ground forces confronted the invaders and lopped off three hundred heads, the wako raided and pillaged at will. On occasion they arrived in fleets of more than three hundred ships, launching what amounted to small invasions of the seemingly defenseless Korean Peninsula. Indeed, its inability to deal with these depredations was a contributing factor in the Koryo dynasty’s eventual demise.

  As he had with the Jurchen, King Taejo sought to gain control over the wako by using a carrot rather than a stick. It was his only real option. Koryo Korea had already proven itself incapable of resisting them by force of arms. They would therefore have to be quelled through appeasement. “[I]f we attend on them with courtesy and nourish them with generosity,” explained the aforementioned Korean envoy, “...then the pirates will all submit.” Pirates were accordingly encouraged to settle down and become farmers in Korea’s fertile southern provinces, where they could in time be absorbed into Korean society. Influential wako leaders were granted court titles, land, incomes, and the promise of a stable, comfortable life, with the understanding that they would guide their followers away from raiding and into more peaceful pursuits.

  They were also offered the opportunity of free trade. This was a tremendous incentive to the wako to give up their raiding ways, the chance to reap substantial profits without risk to life and limb. Prior to this time the Neo-Confucian courts of both China and Korea had taken a dim view of commerce and profit, limiting officially sanctioned international trade in East Asia to the exchange of goods that took place within the context of tribute missions. China would adhere to this policy with regard to Japan for the next century and a half while relations between the two countries lasted, receiving only three ships on each of the sporadic tribute missions sent by the Ashikaga shoguns. Beyond this all trade that passed between China and Japan—and there was a fair bit of it—was handled illegally by smugglers and pirates. For King Taejo to throw Korea’s doors open to international trade was therefore a remarkable change in policy, a significant break with Chinese precedent, and an indication of just how deep his concern was for the survival of his dynasty during its first tenuous years.

  And for the most part it worked. Aside from one or two relatively minor setbacks—for example a resurgence of wako activity in 1419 sparked by a famine on Tsushima—early Choson’s appeasement policy successfully quelled the pirates of western Japan, buying the dynasty the time and the peace it needed to establish itself and ensure its survival.

  By the late 1410s, however, the Koreans had had enough of open doors. The number of Japanese flooding into their country had reached alarming proportions. The cost of free trade had become insupportable, for as the host nation Korea was obligated to cover all the expenses for each and every Japanese “envoy.” Now that the Choson dynasty was established and its legitimacy confirmed, moreover, the need for free trade as a guarantor of stability had diminished, and Korea’s Neo-Confucian government became anxious to once again bring this necessary evil under control. After all, trade was clearly something the Japanese needed more than the Koreans. They were sending more ships to Korea than Korea was sending to Japan. They were more eager to acquire Korean cotton, ceramics, scriptures, and bells than the Koreans were to acquire things Japanese. In the course of the fifteenth century, therefore, Korea’s wako policy, and consequently its Japan policy, shifted away from free trade and wholesale appeasement and increasingly toward limited access and firm control.

  To achieve this the Koreans needed allies at the source of the problem: Japan. They knew that both the Japanese emperor and the shogun could be of little help in controlling pirate and trade activity originating from Kyushu and its offshore islands; their power did not extend much beyond central Honshu. The Koreans turned instead directly to the regional lords of western Japan, in particular of Tsushima. This rocky, mountainous island situated halfway between Korea and Japan had long served as a stepping-stone for traffic between the two countries and had long relied upon trade with Korea for its survival. Its inhabitants were therefore well acquainted with Korean customs and language and had cultural and diplomatic ties to the peninsula that were nearly as strong as its ties to Japan. The Koreans for their part considered the island to have originally belonged to them, a valueless offshore possession known as Daema-do, which had subsequently been inhabited “by Japanese who were rejected by Japan and by people with nowhere to go.”[71] Beginning in the early fifteenth century the Korean court began to move Tsushima further into its orbit by co-opting the island’s dominant family, the So, with the grant of official court rank, a regular income, and the right to send fifty ships a year to Korea for trade. In return the So used their authority to control all Korea-bound traffic and to suppress the wako. Henceforth any ship seeking access to Korea had to obtain appropriate documentation from the So, for which the family was free to charge whatever levy they saw fit. The Koreans, meanwhile, restricted trade access to just the three ports of Ungchon, Tongnae, and Ulsan on the peninsula’s southeastern tip. Any ship attempting to land elsewhere would be considered a pirate vessel and subject to attack. Any ship caught without appropriate documents from the So would be similarly suspect. Three routes north from the coast to the capital of Seoul were also designated specifically for Japanese use. In this manner the Koreans managed during the course of the fifteenth century to funnel all trade through Tsushima, the “Three Ports” (sampo), and the three designated routes, where it could be more easily monitored, limited, and controlled.

  Trade relations with Japan were not broken off entirely, however. That would have abrogated Korea’s kyorin policy toward the Japanese, still regarded by Seoul as essential for appeasing these uncivilized, violent, and potentially dangerous people. The flow of goods between the two countries therefore remained significant, albeit controlled. But the Koreans remained uncomfortable with all this seaborne traffic and economic penetration, and were constantly looking for reasons to reduce the flow of commerce as the Japanese sought ways to open it up. The growing presence of Japanese traders in Korea, for example, would become an issue in Seoul, restrictions would be imposed, the So family on Tsushima would petition to win back lost concessions, and Seoul would eventually relent for the sake of maintaining friendly relations. A gang of pirates returning from China with room in their holds for a bit more loot would strike the Korean coast, angering Seoul into another clampdown on trade, and the So into another round of petition writing. The burgeoning number of unruly Japanese residents in the Three Ports would next become worrisome, and the process would begin again. It became a familiar tug-of-war that would last thro
ughout the sixteenth century, until the start of the Imjin War.

  * * *

  By the middle of the sixteenth century Choson Korea had moved far beyond its anxiety-ridden early years, when its continued existence was by no means assured. It was still plagued occasionally by Jurchen raids in the north and by the odd pirate attack along its southern coast. But these were now aggravating annoyances, not fundamental threats. A navy existed to strike back at the pirates, army garrisons stood in readiness along the northern frontier, and behind them all stood the might of the Ming. Sixteenth-century Choson Korea, at least by its own reckoning, was established, secure, and safe.

  It was also different. Choson Korea was the only nation in the history of the world to adopt Neo-Confucianism as its official state ideology. Nowhere else were the writings of Chu Xi and his predecessors studied so deeply, debated so heatedly, and followed so exclusively. By the mid sixteenth century this fact had served to mold thinking and affect developments on the Korean Peninsula to a more profound degree than was the case even in China.

  The first observable result of this was an ongoing attempt on the part of the country’s officialdom to suppress Buddhism. One of the distinguishing features of Chu Xi Neo-Confucianism, as opposed to the original wisdom of Confucius himself, was that it went beyond expositions on self-cultivation and virtuous conduct and into fundamental metaphysical and spiritual discussions. It was thus regarded by Korea’s scholarly elite as encompassing all the wisdom that a human being required, rendering Buddhism obsolete. Beginning early in the dynasty, extraordinary attacks were launched against this competing ideology, pointing out its defects to highlight Neo-Confucianism’s strengths. “Those Buddhists,” ran one memorial to King Sejong in 1424,

  what kind of people are they? As eldest sons they turn against their fathers; as husbands they oppose the Son of Heaven. They break off the relationship between father and son and destroy the obligation between ruler and subject. They regard the living together of man and woman as immoral and a man’s plowing and a woman’s weaving as useless. They abrogate the basis of reproduction and stop the sources of dress and food.