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

by Samuel Hawley

  Won Kyun, emboldened by their recent victories in June, was eager now to charge into Kyonnaeryang and deal the Japanese another heavy blow. Yi Sun-sin was not. He cautioned that the waters in the strait, averaging just four hundred meters across, were too narrow to allow their ships room to maneuver without fear of colliding with one another and contained numerous submerged rocks and jagged reefs that would be difficult to avoid in the confusion of battle. Yi also did not want to fight the Japanese so close to land, where they could easily swim to shore once the battle turned against them. He therefore ignored Won Kyun’s urgings and held his fleet back in the open waters off Hansan Island, where there was plenty of room to fight and where the only land within swimming distance were a few barren islets offering nothing but slow death by starvation. From here he sent a small detachment of ships forward into the strait to challenge the enemy and draw them out. The ruse, which he had previously used with great effect at the Battles of Sachon and Tanghangpo, once again worked perfectly. The Japanese, spotting the small Korean force, immediately moved to counterattack, whereupon the Koreans turned about and headed back to open water where the bulk of their fleet lay.

  The two fleets met just north of Hansan Island, the Japanese ships strung out in a line, the fastest ships to the fore, the Koreans arrayed in the crane-wing formation they had practiced at Yosu just a few days before. The ensuing battle was a fiercely fought and desperate affair. The Japanese this time were not aboard transports. They had warships and were ready to fight. But the Koreans with their thoroughly protected and heavily gunned vessels were too much for them. Impervious to Japanese arrow and musket fire in their heavy panokson battleships and two or three turtle ships, the Koreans proceeded to blast gaping holes into the hulls of the enemy vessels, set their flimsy wooden pavilions ablaze with fire arrows, and “hailed down arrows and bullets like a thunderstorm.” Yi Sun-sin’s own account of the battle is a litany of death and destruction, the name of each avenging angel carefully inscribed:

  Kwangyang Magistrate O Yong-tam also dashed forward, breaking and capturing one large pavilion vessel. He hit the enemy Commander with an arrow, and brought him back to my ship, but before interrogation, he fell dead without speaking, so I ordered his head cut off.... Sado Commandant Kim Wan captured one large enemy vessel and cut off sixteen Japanese heads including a commanding officer; Hungyang Magistrate Pae Hung-nip captured one large enemy vessel, cut off eight Japanese heads, and forced many others to drown in the water; Pangtap Commandant Li Sun-sin captured one large enemy vessel but cut off only four Japanese heads, because he was more interested in shooting down the living than in cutting off the heads of the dead. Then he chased and destroyed two more enemy vessels, burning them completely; Left Flying Squadron Chief Yi Ki-nam captured one enemy vessel and cut off seven Japanese heads; Left Special Guard Chief Yun Sa-kong and Ka An-ch’ack captured two enemy pavilion vessels and cut off six Japanese heads; Nagan Magistrate Sin Ho captured one large enemy vessel and cut off seven Japanese heads.[304]

  The fighting lasted throughout the day, ranging across the water off Hansan Island and then back into Kyonnaeryang Strait as the battered remnants of the Japanese fleet attempted to get away. Finally, with the onset of darkness and sheer exhaustion, the Koreans broke off their pursuit and returned to the open sea to rest. Of the seventy-three Japanese ships they had encountered, they had captured, sunk, or otherwise destroyed fifty-nine. Most of the fourteen vessels that managed to escape had in fact never really entered the battle at all; they had lagged behind in the initial Japanese assault out of Kyonnaeryang Strait and had then fled the scene upon seeing that the battle was turning against their more enthusiastic comrades. They did not stop until they reached Kimhae, several kilometers up the Naktong River near their home base at Pusan.[305]

  One of these fourteen vessels that got away was a small hayabune (fast ship), carrying fleet commander Wakizaka Yasuharu. According to the Wakizaka family chronicler, “Arrows struck against his armour but he was unafraid even though there were ten dead for every one living and the enemy ships were attacking all the more fiercely. As it was being repeatedly attacked by fire arrows, Yasuharu’s fast ship was finally made to withdraw to Kimhae.”[306] According to Korean accounts, Wakizaka lost his nerve and fled.[307]

  As for the number of Japanese dead, the Koreans had their head count, but it in no way reflected the heavy losses they inflicted that day. For every man beheaded, there were twenty, thirty, even fifty others who must have drowned or otherwise sunk unnoticed to the bottom. Some four hundred men did manage to get clear of their foundering ships and swim to a nearby islet (Japanese records say two hundred), but it was not long after they dragged themselves exhausted onto the shore that they realized they were in a death trap, with no food and no means of escape. The ranking captain among this group, taking responsibility for their plight, sat down on the beach and committed suicide by slicing open his belly. The rest, as Yi Sun-sin had foreseen, were left like “hungry birds in a cage.”[308]

  The news of the Hansan-do disaster found its way back to the Japanese base at Pusan in just a matter of hours and stirred into action the other two naval commanders, Kuki Yoshitaka and Kato Yoshiaki. They immediately set sail with a combined fleet of forty-two ships, but only went as far as the port of Angolpo, twenty kilometers to the west. They hoped to meet the Korean navy close to home, at a place of their own choosing.

  Yi Sun-sin’s patrol boats brought him word of this new enemy movement on August 15, the day after the Battle of Hansan-do. He immediately advanced northeast along the coast of Koje Island, then west toward Angolpo. Sure enough, he found forty-two Japanese ships at anchor inside the port and along the shore, twenty-one of them very large vessels, some with three-story pavilions built upon the decks. The situation was unfavorable for a direct attack, for the harbor was small and the water there dangerously shallow at ebb tide. Yi thus resorted once again to his usual tactic for coaxing the enemy into open water: the tentative advance followed by the feigned retreat. He and Won Kyun proceeded into the harbor to challenge the enemy, leaving Yi Ok-ki with his twenty-three ships to wait in ambush on the open sea. This time the Japanese did not take the bait. Admirals Kuki and Kato, clearly intent on not repeating their comrade Wakizaka’s mistake, held their fleet in place, daring the Koreans to attack them where they lay.

  That is just what Yi Sun-sin did. Upon realizing that the Japanese could not be coaxed out of the confines of the bay, he divided his fleet into small assault teams and sent them in against the enemy fleet in turns, particularly against the ostentatious pavilion ships that were the flagships of the enemy commanders. The sound of battle soon drew Yi Ok-ki out from his place of ambush to join the fight, and together the two Yis proceeded to pound the Japanese to pieces. As at Hansan-do it was a hard-fought battle, for the Japanese did not quickly abandon their ships and flee onto the shore as they had done the month before; they fought the Koreans for hours, rowing their dead and wounded to shore in small boats and returning each time with reinforcements. The battle continued in this manner until sunset. Finally, with most of their ships burned or sunk or awash in the shallows, the remaining Japanese gave up the fight and escaped into the nearby mountains.

  Yi Sun-sin did not finish off all the remaining Japanese ships following the retreat of the enemy inland. He left a few boats intact, for he reasoned that if the fleeing enemy had no means of escape they would turn against the defenseless local population. He then led the way out of the harbor to pass the night. When they returned to Angolpo the next morning they found that the boats that had been left intact were gone, and with them the Japanese who had run into the hills. Yi Sun-sin and his men found evidence in twelve blackened heaps on shore that the Japanese had cremated their dead before making good their escape. “There were charred bones and severed hands and legs scattered on the ground,” Yi recorded, “and blood was spattered everywhere, turning the land and sea red, revealing the innumerable Japanese dead and wounded.”[309]<
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  Over the next two days Yi Sun-sin led his fleet east to the mouth of the Naktong River and then back toward the west, but found no trace of enemy ships. Nor was he able to track down the few boats that bore the survivors of the Battle of Angolpo. These had managed to slip away under cover of darkness, sheltering in the coves of Koje Island before finally returning to Pusan. Among the survivors who made it back to safety on these spared boats were Kuki Yoshitaka and Kato Yoshiaki, who now joined their colleague Wakizaka Yasuharu as the first daimyo commanders to have suffered a serious defeat at the hands of the Koreans. With no enemy fleets left to fight, and with their men exhausted and supplies running low, the three commanders of the united Korean fleet decided to call off their operations and return to their home ports. On the way west they passed the barren islet where the four hundred Japanese survivors of the Battle of Hansan-do had been marooned. These unfortunate men were now growing weak after having gone several days without food, and could be seen sitting dazed on the shore. Since Hansan-do fell under the jurisdiction of Kyongsang Right Naval Commander Won Kyun, Yi Sun-sin gave him the responsibility of finishing off these “hungry birds in a cage.” It was a gift to the glory-seeking Won; all he had to do was lay offshore with his ships until the trapped Japanese were thoroughly weakened and defenseless, then land a party of soldiers to harvest their heads. As an indignant Yi Sun-sin subsequently reported to the Korean court, however, Won Kyun failed in even this simple task. He fled the area soon after being left behind by Yi Sun-sin and Yi Ok-ki, spooked by a false report of the approach of a large Japanese fleet. Left unguarded, the marooned Japanese lashed together rafts from the wreckage of their ships that had by this time drifted to shore, and managed to traverse the few kilometers to Koje Island, where they found food and safety. “In this way,” Yi concluded, “the fish in the cooking pot jumped out, to our great indignation.”[310]

  This second offensive by the Korean navy, like its “Slaughter Operation” in early July, was an unmitigated disaster for the Japanese. Hideyoshi’s navy had lost approximately a hundred ships, this time many of them their best battleships under the command of their most competent admirals, and had managed to sink not even a single Korean vessel in return. They had succeeded in inflicting a few casualties on the Koreans, but according to Yi Sun-sin’s count these totaled only 19 dead and 114 wounded. No reliable figure exists as to Japanese casualties. The heads that Yi’s men cut off and the box of salted ears they sent north to the court as evidence of their valor in no way reflected the full extent of the carnage they had inflicted. Following the war, however, a Korean named Che Mal, who had been captured in the early days of the invasion and taken to Hideyoshi’s headquarters at Nagoya to work as a clerk, stated that he had seen reports sent from Tsushima at about this time that placed the total number of men killed in battles with the Korean navy at over 9,000. [311]

  Whatever the true number, it is clear that Toyotomi Hideyoshi regarded these losses as unacceptable. It is also clear that he now doubted the ability of his navy to overcome Korean resistance in southern waters and establish the much-needed supply route around the southwestern tip of the peninsula and north through the Yellow Sea. On August 23 he ordered naval commander Todo Takatora forward from Iki Island to reinforce his colleagues in Korea, and dispatched orders to Pusan halting naval operations along the southern coast.[312]

  * * *

  Yi Sun-sin’s victories in the Battles of Hansan-do and Angolpo have been described as one of the main factors leading to the ultimate failure of Hideyoshi’s campaign to take Korea and conquer China. This assessment was first forwarded by Korean prime minister Yu Song-nyong in his Chingbirok, an account of the war that he wrote some time between 1604 and his death in 1607. Of Yi Sun-sin’s Hansan-do and Angolpo campaign Yu had this to say:

  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.

  Now that Cholla and Chungchong Provinces had been secured, moreover, it was possible for the government to maintain traffic and communications between this southern region and the coasts of Hwanghae and Pyongan Provinces to the north, thus paving the way for national rejuvenation. Chinese waters were also secured, particularly the coastline around Liaodong and Tianjin, thus giving the Ming government time to send troops overland to help Korea to beat back the invaders. All these accomplishments must be attributed to nothing but Yi Sun-sin’s victory at Hansan-do. Indeed, it must have been an act of divine providence.[313]

  Yu’s assessment of the importance of these events has been generally accepted by modern historians. Some have seen Yi Sun-sin’s naval success as the most important factor leading to the failure of Hideyoshi’s campaign;[314] others have described it as one factor among several. But few have discounted it altogether.

  And rightly so. There can be no doubting that Hideyoshi’s armies in Korea needed reinforcements if they were to continue their advance with any degree of confidence. As things currently stood there were fewer than thirty thousand Japanese troops in the north, not nearly enough to slash their way to Beijing. Hideyoshi launched his invasion with the clear intention of sending these reinforcements north by ships via the Yellow Sea. The only alternative, to march everyone and carry everything over 650 kilometers of mountainous roads and trails, would be far too slow and laborious. In preventing the Japanese navy from entering the Yellow Sea, therefore, Yi Sun-sin was not merely making a nuisance of himself off to one side. In stopping the Japanese navy’s westward advance he had thrust a wrench into the heart of Hideyoshi’s war machine. In the coming weeks and months the Japanese would encounter other obstacles in Korea, principally the arrival of large numbers of Chinese troops and determined resistance from local guerrilla fighters. The rout at sea, however, would remain the first serious setback in their planned invasion of the mainland, and as such possibly the most important one, for in blocking the flow of reinforcements, it significantly weakened their land forces and in turn rendered them that much more vulnerable in the land battles to come.

  CHAPTER 13

  “To me the Japanese robber army will be but a swarm of ants and wasps”

  If trouble arises within a hundred li, do not spend more than a day mobilizing the forces. If trouble arises within a thousand li, do not spend more than a month mobilizing the forces. If the trouble lies within the Four Seas, do not spend more than a year mobilizing the forces.[315]

  Wei Liao-tzu (Master Wei Liao)

  4th century B.C.

  It took the Ming Chinese nearly three months from the start of the Japanese invasion to recognize the gravity of the situation in Korea. The decision to mobilize the empire’s armed forces was not made until August 8, 1592. One of the reasons for this slow response was a lack of understanding of what was actually taking place on the peninsula to the east. At first the Chinese assumed that the frantic appeals for help from the Koreans were merely an overreaction to an unusually large wako pirate raid, the kind that had plagued the Koreans and the Chinese for centuries past. Once they realized that Hideyoshi’s invasion was in fact much more than this, the government in Beijing then began to suspect that the whole thing was a plot that the Japanese had cooked up with the Koreans. How else could the incredible speed be explained with which the Japanese were advancing toward China’s eastern frontier? Could they fly? Or were the supposedly loyal Koreans actually helping them along?

  The Chinese were also preoccupied with pressing matters closer to home during these opening months of the war, notably the army-mutiny-cum-Mongol-uprising that had its northwestern frontier in a tumult beginning in March of that year. At the very moment when the Koreans were clamoring for military assistance in the east, Beijing was busy dispatching reinforcements to the northwest to put down this serious threat to internal
security. Throughout the summer and fall of 1592 this so-called Ordos Campaign took almost all the armed strength that China could muster, including the army in Liaodong, the province nearest to Korea.

  Beijing was not totally without resources during these trying months. In July it dispatched a token force of a thousand men under Tai Zhaobian and Shi Ru to aid the Koreans. This small army met King Sonjo on July 26 at Kwaksan, fifty kilometers inside the Korean border, and accompanied him and his entourage to the border town of Uiju on the Yalu River, where it remained as his personal bodyguard. From there King Sonjo continued to send messages and envoys west to Beijing, imploring the Wanli emperor for more help in driving the invaders back. The Chinese eventually responded in August by raising a second army, this time of five thousand men, mostly cavalry and spearmen, under the command of General Zhao Chengxun, regional vice-commander of Liaodong. The decision by this time had been made to mobilize the empire’s armed forces, but that would take months. For the time being this was as large an army as the Chinese could send.

  General Zhao had recently returned to his home base in Liaodong Province from the northwestern frontier, where he had enjoyed great success in putting down the rebellious Mongol tribes in the ongoing Ordos Campaign. The uprising there had still not been completely stamped out, but the rebels were now under siege in the city of Ningxia, and it was only a matter of time before they were overrun, their ringleaders executed, and their heads placed on display. Zhao was thus the man of the hour in Beijing, and was brimming with confidence as he led his army east to Korea. Upon arriving at Uiju in mid August, he assured King Sonjo and members of the Korean government that now that he was on the scene the Japanese problem would soon be solved. Upon learning that the enemy was still holed up at Pyongyang, he even went so far as to raise a glass of wine and exclaim, “Heaven is indeed good to keep them there for me.” The Korean generals cautioned Zhao not to take the Japanese so lightly, but he brushed their concerns aside. “To me,” he replied, “[the general] who, at the head of three thousand fighting men,...annihilated a Mongol army of one hundred thousand, the Japanese robber army will be but a swarm of ants and wasps. They will soon be scattered to the four winds.”[316]