Admiral Yi Sun-shin, the Turtle Ships and Korean Culture in Early Modern World History

Written by Marc Gilbert
Professor of History, North Georgia College & State University

Korea, along with Southeast Asia and the Pacific Basin, has long been relegated to the periphery of global studies. It is usually perceived as a merely a “satellite” of Chinese civilization and, in the modern period, as a victim of indigenous Asian imperialism, Japanese as well as Chinese. Close study of such marginalized peoples and regions are valuable in offering insight into the histories of their more powerful or influential neighbors as well as their own. However, the periphery is often where the real action is in terms of offering intriguing personalities and events that illuminate larger patterns of world history or rationales for their modification or re-examination by scholars. This is the case of Admiral Yi Sun-shin and his Turtle ships, which link Korea and world history in ways it is hoped instructors and students alike will find both fascinating and rewarding.

The life and service of Korean Admiral Yi Sun-shin (1545 – 1598) and his role in early modern Korean politics and the development of early modern naval technology expand our understanding of world history in several ways. It offers an exciting example of technological change in Asia at a time when the treatment of such change in courses on world history usually shifts to Western Europe and thus can assist in managing the well-established Eurocentric tendencies to approach modern world history through European examples. Because Yi Sun-shin also introduced a revolutionary naval warfare that initiated the “modern” naval forces and combat style still prevalent today, and this revolution was pursued simultaneously by Sir Francis Drake and John Hawkins in the West, it can also serve as a classic example of “worlds together, worlds apart” parallelism, as well as change over time. This parallelism, however, reaches beyond the late sixteenth century. The Japanese foes of Admiral Yi Sun-shin inflicted some of the worst atrocities of early modern world history, especially upon women, during the Japanese invasion of Korea that Yi Sun-shin helped defeat. These atrocities offer parallels with both the siege of Masada of Jewish-Roman lore and the twentieth century exploitation of the people of the Korean peninsula that still casts a shadow over Japanese-Korean relations. These atrocities also, if under unfortunate circumstances, permit the incorporation of women into the discourse over Yi Sun-shin’s life and service.

Though centuries after his death even Yi Sun-shin’s Japanese foes regarded him as beyond comparison with any other naval hero, students of Yi Sun-shin’s life and work will see immediate parallels between his career and that not only of Drake and Hawkins, but also of England’s Lord Nelson and America’s (and Russia’s) John Paul Jones. All were great innovators of naval strategy, but suffered disgrace and disappointment while helping to rescue their respective nations from foreign foes. Yi Sun-shin’s struggles may also be compared to Britain’s Lord Jackie Fisher and Sir Winston Churchill, Germany’s von Tirpitz and America’s James “300 ship navy” Webb, all of whom who also fought sustained battles with political authorities that had profound implications for the good and for the ill of their respective countries.

Yi Sun-shin’s own struggle with factions at the Korean court speak volumes about contemporary Korean culture, but it also helps unpack the nature of the common struggle all innovators face, which for Yi Sun-shin revolved around questions of personal ethics and responsibility. Today, when ethnical concerns are routinely dismissed with reference to the need to complete in a world largely devoid of them, Yi Sun-shin’s life demonstrates that a truly efficient society depends on personal ethics, honor and the ability of officials to serve ends rather than ideology or careerism. Perhaps what matters more is that students will find that Yi Sun-shin’s life and struggles as a technological innovator offer insight into the struggles of all such pioneers in world history, from Galileo Galilei to Steve Jobs, and might even see themselves in their effort to succeed their own turbulent software-driven world. Teachers will find the resources for exploring the subject readily available and sufficiently attractive to not only employ in their classroom, but decorate it, as will be seen from the documents and resources, detailed below. These resources include projects suitable for grades 9-12 and for university undergraduates, as well as research materials for more advanced study.

The following narrative, drawn from a variety of sources mentioned in the bibliographic section, is designed to introduce the images and documentation that accompany them. It is followed by study questions, exercises and lesson plans that may be used to measure student comprehension and promote further inquiry.

Life of Admiral Yi Sun-shin (李舜臣)

Lord Admiral (Chungmugong) Yi Sun-shin was born into a wealthy aristocratic family in April 28, 1545, the same year as Sir Francis Drake, near Seoul, Korea. He married in 1564 and two years later began the study of the traditional Korean military arts: archery, horseback riding and swordsmanship. This was a somewhat unusual interest for a son of the Chosŏn elite, who shared the Chinese Confucian view of military service as an inferior occupation. Though male Koreans owed the Chosŏn state three months of military service every five years until the age of sixty, “from the earliest times, the yangban (aristocratic landowners) contrived to avoid this obligation, and even to evade military taxes.”(Cited from Thor May’s review of Yang Sung-jin and Lee Nam-hee, Click on the Click into the Hermit Kingdom, Seoul: Dongbang Media Co. Ltd, 2000, review dated January 30, at Click on into the HermitKingdom, was originally a CD-ROM exploration of Chosun lore and its printed version is just as effective as a major resource for the study of that dynasty.)

Yi Sun-shin and his wife had three sons: Hoe (born 1567), then Yo (born 1571) and then Myon (born 1577). His legendary drive and stamina were first noted in 1572 when, during his military examinations, he fell from his horse and broke his leg. He then completed the riding exam after rigging a splint out of a willow branch. After passing his examinations, he served in various staff and field commands. Since the Korean military service made no distinction between branches of service, it is not unusual that he was assigned in 1580 as a naval commander the southern tip of Korea. However, two years later he refused to compromise his high personal standards of conduct, thus earning him the enmity of his immediate superiors, who stripped him of his command; then as now, one’s superiors cannot handle the truth when it reflects badly on their own performance.

Yi Sun-shin nonetheless secured an appointment as acting commandant of Konwon fortress on Korea’s northern frontier. Shortly after he took charge there, the post was assaulted by Manchurian (Jurchen) forces. During this battle, Yi Sun-shin brilliantly lured his opponents into a trap, captured the Jurchen leader and defeated his forces. However, at the end of the same year, Yi Sun-shin’s father died and Yi Sun-shin was obligated to resign his post to fulfill his filial duties as a mourner, which, according to Confucian Korean tradition, lasted three years. A year after returning to service in 1586, he again saw action against Manchurian invaders. While leading a counter-attack, he was wounded in the leg by an arrow, but he removed it himself without letting anyone else see his injury. He did so out of a concern that the sight of an injury to their commander might demoralize his troops, a principle that he literally carried to his grave.

Though Yi Sun-shin was always careful to attribute his successes to others and share such glory as came his way, his superiors grew jealous of his achievements and had him arrested. Since Yi Sun-shin refused to confess to the false charges brought against him, even under torture, his accusers had to settle for stripping him of his rank and imprisoning him. Fortunately, the King freed him under the condition that he fought as a common soldier. After the ever-humble Yi Sun-shin bore this demotion without complaint, the King again intervened and pardoned him for his non-existent crimes in 1588, the same year the Spanish Armada launched its attack on Britain.

After a year’s leave, Yi Sun-shin returned to his country’s service as a staff officer and then as the King’s personal bodyguard and messenger. Due to the King’s continuing interest in his career, he was twice made a magistrate and re-appointed as a commander on the northern frontier, but such patronage only attracted more enemies, who forced his transfer from one post to another. Fatefully, in 1591, Yi Sun-shin’s merry-go-round of appointments led to his arrival in the seaport of Yosu as Commander of Cholla Left Naval Station [whereas the British Royal Navy is divided in its command structure into Admirals of the Red and White, Korea’s naval forces were divided between commands labeled Left and Right.] In Cholla, Yi Sun-shin began to address a perennial threat, Japanese piracy, which turned out to be nothing but the prelude to the greatest military challenge yet faced by the Korean armed forces, the Japanese invasion of 1592 – 1598.

The Japanese Challenge

For centuries the Korean coastline had been menaced by the Japanese. In 1393, The Kings of Silla (668 – 935), the first dynasty to rule over all of the Korean peninsula, carved out a Buddhist cave grotto at Sokkuram in the hills above their capital, within sight of the Sea of Japan [the Korean “East Sea”]. The grotto provided shelter for one of the world’s finest stone-carved images of the Buddha (751). As Sokkuram was a royal chapel and the Buddha was graced by a jewel mounted on his forehead that caught the dawning light, it has been argued that Silla’s rulers were so “mindful of Japan and the possibilities of invasion” that Sokkuram had been constructed to serve “as protector of Korea against invasion.”(Don Liu,“The Future of Korean-American Community: Challenges and Prospects” at

It was thus something by way of a pre-emptive strike that Korea supported the Mongol invasions of Japan in 1274 and again in 1281. The failure of these assaults helped expose Korea to centuries of attacks by Japanese pirates in league with Chinese and even Korean freebooters (collectively known as Waegu). One such attack resulted in the sacking and burning of Seoul in 1371, which may have hastened the fall of the Koryo dynasty in 1392.1

Mindful of the barbarity and destruction long wrought by its sea-borne enemies, the ruler of the succeeding Chosŏn dynasty (1392 – 1910), King Sŏnjo (1567 – 1608), was in no doubt over the seriousness of a threatening communication he received from Korea’s old naval threat, Japan. Possibly the greatest of all Japanese warlords, Toyotomi Hideyoshi had recently achieved domination over virtually all of Japan, but, as he wrote to King Sŏnjo in 1592, this was not enough to quench his self-admitted lust for the conquest. In terms of sheer ego, these remarks parallel that of a much earlier would-be conquer of the “East,” Alexander the Great. F. W. Seal has noted that:

Many attempts have been made to explain the reasoning behind Hideyoshi's efforts to conquer Korea. Some have suggested that he was intentionally bleeding away the power of the daimyo [land barons], so as to strengthen the security of the Toyotomi. This theory has always been rather popular, but overlooks the fact that the majority of daimyo who would fight in Korea were staunch supporters of Hideyoshi, including Kato, Konishi, Mŏri, and Chosokabe. By way of comparison, some less trustworthy elements never set foot in Korea, including Tokugawa Ieyasu and Date Masamune. Another slightly different but comparably popular suggestion has Hideyoshi invading Korea to provide an outlet for his daimyo, lest they have the time to begin plotting against their new overlord. Both arguments are essentially sides of the same coin, and are both weakened by the fact that most of the daimyo east of Kyoto never saw a day of service on the Korean mainland. The most likely explanation for Hideyoshi's campaign on the Asian mainland, then, was the same driving force that had seen him to rise to become Kampaku and had intoxicated so many other would-be conquerors: ambition.(For the Japanese context of this invasion, see and an essay by Cesare Polenghi,“The Reasons, the Chronicle and the Consequences of the Japanese Invasion, 1592-1598,” at

Hideyoshi, who sincerely prided himself on his diplomatic skills, informed King Sŏnjo that it was his intention to conquer China and called upon Korea to “help clear my way” and thus “save her own soul . . .”2 However, much like the King of the Belgians in the Great War of 1914 -1918, who refused to allow the German army to march through his country en route to defeat France and hence effect the domination of all of Europe (including his own state), Sŏnjo declined to permit his kingdom to serve as a smooth path of conquest for Hideyoshi who, like Kaiser Wilhelm, would also have inevitably sought Korea’s own submission to his rule.

Hideyoshi responded to Sŏnjo’s defiance by launching one of the most destructive military assaults Korea has ever experienced, known as the Imjin Wars (1592 – 1598). The first assault wave of over 24,000 men, carried in over 800 ships, arrived at Pusan in May of 1592. Remarkably, this initial force was commanded by the Christian Lord Konishi Ukinaga and is believed to have been largely composed of Christian troops. These units were later joined by the Buddhist warrior Lord Kato Kiyomasu as the force grew to more than 150,000 men armed with thousands of the most modern gunpowder weapons, called muskets, which the Koreans lacked. This enabled them to march north so swiftly as to reach the Chosŏn capital at Seoul within three weeks, even though they paused along the way to destroy virtually every Buddhist monastery and monument they encountered. Once Seoul was occupied, Japanese army leaders visited the Unjŏngsa temple in Hwanghak-dong where female monks lived. There they raped, then burned the temple as they left, leaving all the women homeless and many pregnant. Several of the pregnant monks built a tent house where they gave birth to the children born of the Japanese assault. The local population called the site “a place for foreign pregnancy.” Years later, a pear tree was planted in the area and it flourished. People then started calling the site It'aewon, meaning pear and big place, and by that name the area remains today as much a part of Seoul’s urban life as is the Marais in Paris or Greenwich Village in New York.(For the legend of It’aewon, see

Only the Korean fortress-city of Chinju had held out against the initial Japanese onslaught. Accordingly, Hideyoshi had sought to make an example of it, ordering a fresh assault "to take the city at all costs and punish it severely." The subsequent fall of the city, according to Donald H. Liu, “is often categorized as the bloodiest, cruelest, and most full of atrocities committed by the Japanese soldiers,” the memory of which “is scarred deep into the Korean psyche, an annihilation comparable to that of the Jews of Masada after the fall of Jerusalem to Roman troops.” Liu has written that:

When I was American Consul in Pusan in 1992, on the four hundredth anniversary of the invasion, I saw a Korean opera commemorating the fall of the South Fortress at Chinju, where Korean soldiers all fought to the death and Korean women flung themselves from the ramparts rather than be sexually assaulted by the invaders. Koreans tell me that the custom for Korean women to carry a small encased dagger, now for decorative purposes, when they wear the traditional hanbok dress, stems from this time of invasion.(See Don Liu, “The Future of Korean-AmericanCommunity: Challenges and Prospects’” at

Having established a parallel between Masada and Chinju, Lui mentions an event of patriotic female self-sacrifice that world historians have found in many other cultures:

Chinju's defeat evolved into a final victory of sorts due to a young kisaeng [a female entertainer or courtesan] girl named Nongae. Likely a country girl with no family name, she was sent for along with the other captured kisaeng to entertain the conquering Japanese officers gathered on the heights above the city. A pavilion crowned the highest promontory and there the most beautiful girls came to entertain the victorious generals. When the gaiety had reached its peak of drunken exaltation, Nongae embraced one of the generals in a long and passionate kiss, some say locking the five rings she wore on each hand in a stranglehold . . . clutching him tightly, she threw herself and him into the river to be dashed as their bodies hit the rocks below. There is a shrine to Nongae in Chinju. For her self-sacrifice she remains highly regarded as a national heroine.(Dennis P. Halpin, “Human Rights in South Korea: Confucian Humanismversus Western Liberalism,” at

This tale illuminates the key role the wars with Japan and Manchus played in Chosŏn gender relations:

To protect their husbands and sons from being killed by the invaders, women directly confronted and resisted the Japanese and Manchu soldiers by any means such as throwing stones and sticks and biting them. The bold courage of Chosŏn women resulted in the merciless killings of these women and after the two great wars swept through the nation, women no longer remained as the quiet and obedient figures. The women’s awareness began to grow as they realized that they had the confidence to do things by themselves and they should not be limited solely to the idea of becoming the wise and virtuous mother and wife.

Admiral Yi Sun-shin’s response to the invasion of his homeland was as dramatic and reflects the same militant nationalism as the tale of Nongae. Since that response was also redolent of Korean patriarchy and a host of prevailing social values as well as martial spirit and actually succeeded in driving off the invader, it was to earn him even greater accolades as a savior of his nation.

Yi Sun-shin Takes Command

Yi Sun-shin was neither caught unaware nor unprepared by the Japanese assault. Upon his arrival in southern Korea, Yi Sun-shin immediately set about his new duties as naval commander. He had long studied the strengths and weaknesses of both Korean and Japanese naval practices and weapons. Japanese naval power was based on their greatest strength — expert samurai swordsmen and bowmen. To maximize their strength, the Japanese built broad-beamed ships that carried a large number of soldiers. Their strategy, which, as one modern authority has noted, was as old as the Battle of Salamis in 480 BCE., was to approach enemy vessels as closely as possible and rake them with arrow fire until the enemy’s decks were clear enough for the Japanese swordsmen to sweep aboard and do battle with the remaining opponents. Stiff resistance was met with fire arrows fired by the bowmen, though still necessarily firing at close range. More recently, though the Japanese had chosen not to mount more than one cannon to each of their ships, they were filling their vessels with musketeers. The range of Japanese muskets was no greater than that the bowman could achieve with their arrows, but the bullets fired by muskets had much greater penetrating power. According to some Japanese sources, these ships, called Atakebune, were ironclad, very slow and thus ill-suited to handle anything more than coastal operations.

Like the builders of the caravel in Western Europe, the Koreans built ships with “castles” or enclosures to better protect their crews from attack by arrows and muskets. Korean records suggest that a ship called a “turtle boat” [Kŏbuksŏn] was under construction as early as 1414, but by the time of Yi Sun-shin’s appointment, no Korean ship of any type was capable of defeating the Japanese. Yi Sun-shin lost no time in urging the local boatyards to rectify this problem. Though there is no evidence by which to gage their progress, within months they produced a vessel “that so thoroughly nullified the enemy’s weapons and tactics that, in Yi Sun-shin’s hands, only a few of the new ships were necessary to secure naval dominance in the seas around Korea.” His ultimate success was to become so entwined with Korean national pride that they led to often outlandish claims. As Underwood notes:

It is often asserted that [the Turtle Ships] were the world’s first armored or ironclad vessels; some modern writers even describe them as the world’s first submarines! They certainly were innovative in design, but, despite Korean’s brilliance in metal-working, it is unlikely that the Turtle Ships carried any metal armor — their offensive advantage over the Japanese was their speed and multi-cannon armament: heavy ship armor would have slowed the ships and, in combination with the as many as 40 cannon they mounted, would have lent them so great a weight as to sink the ship. Armor plates on the ship’s upper deck would have certainly done so, as the ships were without keels and would have been so top-heavy as to have easily capsized.3

Since there were probably not many more than a dozen of these vessels operational at one time and possibly as few as three in service on occasion, Underwood contends that “the emphasis on the originality of the ship’s design “diminishes Admiral Yi Sun-shin’s far greater achievement. It was his development of thoroughly modern ship-fighting tactics that perfectly exploited his new ship’s design that was a greater cause of Korea’s naval success against the Japanese than the ships themselves.” After all, “when Yi Sun-shin was temporarily superseded in command, his successor was ignominiously defeated while deploying the same forces in battle. Yi Sun-shin’s true genius lay in the “new ships’ design as an expression or extension of Yi Sun-shin’s revolutionary tactics.”4

Yi Sun-shin’s design for his Turtle Ships addressed the fundamental problem posed by the Japanese tactics and weapons: how could they avoid being shattered by close range bow and musket and fire and boarded by the world’s best swordsmen? The answer lay in speed and longer range fire-power. Yi Sun-shin’s Turtle ships were almost twice as long and half as wide (110 feet by 38)5 as their Japanese counterparts, making them much faster through the water. And since his cannon could outrange Japanese musket balls, he could effectively engage his enemy at his discretion, standing off from them and pounding them into small pieces of flesh and wood. These boats had as many as forth 3-inch (or thirty-six pound) cannons firing through hatches along its side. Another cannon was mounted in the mouth of the good luck-attracting dragon's head carved into the prow, while still another was mounted beneath the stern transom.

In retrospect, Yi Sun-shin’s development of the first “stand-off” weapon was a simple enough proposition, except that Yi Sun-shin shares with Sir Francis Drake credit for being the very first men to abandon the grapple-board-and have-at-them style of naval fighting that had gone unchanged for perhaps two thousand years and adopt in its stead the form of naval warfare later pursued from Trafalgar to Jutland and from Cape Matapan to Leyte Gulf.

Yi Sun-shin anticipated that his enemies would ultimately adjust their own war-fighting strategy to meet this new challenge: Japanese ships came to mount more cannon of their own. However, like Drake, Yi Sun-shin always remained a step ahead of his foe. His forces were, for example, also the first to adopt an “in line ahead” (Yi Sun-shin called it “holding onto each other’s tail), a sailing protocol that enabled each ship to bring its guns to bear upon the same targets as they passed them in turn.

He also deployed a tactic called ‘drawing the fish into the net,” with the feigned retreat to in order to draw entire Japanese fleets into position to attack, so few could avoid combat or otherwise escape the engagement. It is for this reason relatively few Japanese ships survived an engagement with Yi Sun-shin forces unscathed.

As brilliant as his tactics may have been, Yi Sun-shin also knew that he could not always dictate the rules of engagement. There would be times when his forces would have to come to close quarters with Japanese ships and face their intense close-in fire and skilled boarding parties. Yi Sun-shin addressed this problem through the very structure of the Turtle ships themselves. Building on evolving Korean practice of cannon use (introduced from China in 1373) and protection for crews, Yi Sun-shin entirely enclosed his oarsmen and gun crews in iron-bound four-inch thick wood deck planking impervious to arrows and musket fire. A recent work by admittedly non-naval architects argues that the exposed upper planks may have been covered by very thin sheets of metal, which may have given rise to the idea that the ships were made of metal or armored,(Shim Sun-ah, “New Book Sparks Controversy Over 'Turtle Ship,”Yonhap News Service, February 2, 2005.) but Korean deck wood seems to have been more than adequate to this task and obviated the added weight. However, more importantly, and most likely Yi’s own idea was that the curved upper-most deck acted as a roof protecting the crew, who were trained to shove their own spear points through slots in the decking that were concealed by thatch strewn over the deck. It is though that “Japanese soldiers leaping upon that decking would find themselves either impaled upon these blades or sliding off the rounded upper-surfaces into the sea.”

Into Battle: 1592

Having prepared his new vessels and trained his crews, Yi Sun-shin moved around the peninsula to relieve the devastated fleet of the Korean commander on the southeast coast of Korea, Wŏn Kyun (1540 – 1597), who, naturally enough, resented his rescue and plotted to undermine Yi Sun-shin at court. However, Yi Sun-shin focused on the foreign foe and crushed them in a series of naval battles, one so intense that the admiral was wounded, which he concealed from his men. This campaign ended with the triumphant victory at Hansando in 1592, which Yi Sun-shin’s nephew describes as follows:

On the eights of Seventh Moon, hearing of the enemy’s departure from Yangsan toward Cholla province, [Yi Sun-shin], Yi Sunshin Ok-ki [Commander of Cholla Right Naval Station], and Won Kyun [Commander of Kyongsang Right Naval Station] sailed to Kyonnaeryang (in Kosong), where they saw seven enemy vanguard vessels advancing in their direction, followed by many other crafts spread out all over the sea. Ch’ungmugong said, “Here the sea is narrow and the shallow harbor unfit for battle, so we must lure them out to the open sea to destroy them in a single blow.” He ordered his warships to pull back with feigned defeat till the jubilant enemy vessels pursued our fleet as far as the sea off Hansando, where they concentrated their total strength. Ch’ungmugong waved his flag, beat his drum and shouted the order to attack. In an instant, our warships spread their sails, turned round in a ‘Crane-Wing’ formation and darted forward, pouring down cannon balls and fire arrows on the enemy vessels like hail and thunder. Bursting into flame with blinding smoke, 73 enemy vessels were soon burning in a red sea of blood. This is called “The Great Victory of Hansando.”(Cited at

As mentioned above, Hansando is in strategic terms considered the equivalent of the naval success of the Greeks against the Persians at Salamis, because at Hansando as at Salamis, the tide of an invasion was stemmed, in this case because Yi Sun-shin had destroyed the logistical supply line, the seaborne transportation of men and materials, that was essential for Japanese operations in both Korea and China.

The War at Home, 1594 – 1596

Such victories led to Yi Sun-shin’s promotion to Supreme Naval Commander of the Three Provinces. He had little time to enjoy it. After a dutiful visit to his mother (who, in an example of growing political awareness among Chosŏn women, welcomed him and then immediately urged him to return to battle in defense of the Korean people), he returned to court to find King Sŏnjo negotiating for Chinese support against the Japanese. Yi Sun-shin opposed these negotiations out of traditional suspicions of Chinese designs on Korea. He told the court that he was “a subject of Korea, and for justice’s sake I cannot live with these robbers under the same heaven.” He then endured a personal bout of typhoid and had to confront a devastating outbreak of plague among his naval forces. Yet, Yi Sun-shin subsequently led his fleet to a major victory against the Japanese at Changmunp’o in 1594.

However, that victory did not prevent his rival Won Kyun from successfully exploiting Yi Sun-shin’s outspokenness at court and the resentment among others like himself of Yi Sun-shin’s achievements. He helped arrange a test of Yi Sun-shin’s loyalty that was impossible for him to pass. In 1597, Yi Sun-shin was sent to destroy a Japanese naval force under such conditions that he could not but fail. Yi Sun-shin knew this, but the court was so set against him that there is no way he could decline or otherwise prevent his “failure” to complete this assignment from being interpreted as anything other than as an act of disloyalty. As a result of this gambit, the command of Korean naval forces was given to Admiral Wŏn Kyun and Yi Sun-shin was dragged off to Seoul in a cage on an ox cart, much to the dismay of the public. People reportedly lined the route of his journey to protest the humiliation of their hero. After a time, Yi Sun-shin was released to serve as regular soldier. He executed these humble duties with great dignity despite enduring another blow: the loss of his mother.

Return to Battle, 1596 – 1598

In Yi Sunshin’s absence, Hideyoshi launched a second invasion of Korea in 1596, sending over 140,000 men in over 1,000 ships to land at Sosang Harbour. This force easily crushed Wŏn Kyun’s fleet, a defeat made bitter by Wŏn Kyun’s attempt to flee the scene of battle, after which he was caught and beheaded. Wŏn Kyun’s disgrace enabled the court to rehabilitate Yi Sun-shin’s reputation and once again asked him to serve as Supreme Naval Commander, though the King contemplated the abolition of what little remained of Yi Sun-shin’s former forces only 12 vessels and only 120 sailors survived Won Kyun’s command. Yi Sun-shin, however, prevented this outcome by declaring that, “After all, I still have 12 ships! As long as I live, [our] enemies will never look down on us.” He used these well enough to resume his victorious assault on the Japanese, though his third son, Myon, was killed during these campaigns.

In 1597, Yi Sun-shin’s naval forces, together with Chinese land forces acting in concert with Korean forces (which included guerilla units made up of Buddhist monks), drove the Japanese into a narrow perimeter around the southern port of Pusan, from whence they had no option but a fighting withdrawal by sea. To prevent this, with the nation’s fate at stake, Yi Sun-shin set aside his reservations and accepted the support of a Chinese naval force under the Ming Admiral Chen Leng, who did Yi Sun-shin the very politic and high honor of serving under the Korean admiral’s command. Together, these forces ended any Japanese hopes even for an honorable retreat. In November of that year, Yi Sun-shin was engaged in major battle at Noryang against the Japanese that led to the destruction of two hundred out of Japanese five hundred ships engaged, with many more left crippled, virtually ending the seven years long Korean debacle which is thought to have hastened the death of Hideyoshi, “who reportedly died of a broken heart over these losses.”6 Yi Sun-shin’s nephew recounts that at the very turn of the tide of this battle in Yi Sun-shin’s favor, with the admiral to the fore urging his men in an assault on a Japanese vessel, “a stray bullet from the enemy vessel struck him. “The battle is at its height; do not announce my death!” With these words, he died.” His eldest son, Hoe, and Hoe’s cousin Wan then removed Yi Sun-shin’s body to his cabin and returned to the battle “banging the war drum and waving the battle flags, thus ensuring nobody knew of Yi Sun-shin’s death and ensuring a final victory.”(See Sun-Shi_sun_shin_adm/YiSun-Shisunshin.html)

After his death, Yi Sun-shin was given the title of “chivalry and honesty.” Some students of Korean history have come to regard him as a throwback to the Hwarangs. These were bands of Buddhist/Daoist martial arts “knights” who followed a code of conduct then over a thousand years in the past.(For a brief history of the Hwarangs, see See also Ruth S. Hunter, “Admiral Yi Sun-Shin” Warrior Spirit,” at In Yi Sun-shin’s time, their Code was considered passé by the Confucian-influenced scholars who values dominated the Chosŏn court. Whether or not Yi Sun-shin lived according to the Hwarang Do, Yi Sun-shin:

believed in three essentials for the warrior: humility, discernment, and courage. He embodied all of them, and lived with integrity throughout his life. When Admiral Son Ko-i died in 1598, a letter was found among his possessions. It was from Yi Sun-shin, and in it he wrote, "My life is simple, my food is plain, and my quarters are uncluttered. In all things, I have sought clarity. I face the troubles and problems of life and death willingly. Virtue, integrity and courage are my priorities. I can be approached, but never pushed; befriended but never coerced; killed but never shamed.(See

Assessments of Yi Sun-shin’s Career and the Politics of Memory

After his death, Yi Sun-shin was given the title of “Lord of Loyalty and Chivalry” or Chungmukong, 충무공; 忠武公. King Sŏnjo had a shrine built to honor him at Chungyŏlsa in 1606, which was later rebuilt and expanded. In 1706, a shrine called Hyŏnchungsa near Yi’s family home close to the port city of Asan was dedicated to his memory. The site includes an exhibition hall which displays a portrait of Admiral Yi, a painting describing his life, his War Diary, his long sword, an archery field and a reconstruction of his private residence, which can be virtually visited at In 1832, a marker was erected on shore close to where he died, to which was later added a beautiful pavilion.

Sadly, Yi Sun-shin’s naval innovations became no more than the subject of honored memory. Like their Ming allies, the Chosŏn dynasty became preoccupied with landward threats, such as the renewed Manchu aggression of the seventeenth century and there was no real naval development thereafter. Still, by his thwarting of Hideyoshi’s Pan-Asian ambitions, Yi Sun-shin had not merely sustained the tradition of Korean independence, but helped set the course of East Asian history for generations. Had Hideyoshi achieved his goal of conquering the Chinese Ming Empire, the Manchu invasion may have run a different course and with it, much of world history.

As the impact of his life on Korean history became better understood, Yi Sun-shin came to be increasingly memorialized until he emerged as a symbol of honesty and self-sacrifice. Given the court intrigues, corruption and mismanagement that characterized Chosŏn politics, it is little wonder that when Korea emerged from Japanese colonial domination after the Second World War, its new government sought to promote the impeccable Yi Sun-shin as the hero for modern Koreans to emulate. President Park Chung Hee rewrote the plaques for the Hyŏnchungsa shrine in 1965. In 1966, the government expanded the shrine's compound to 342,112 square meters and declared it a national shrine. It was designated an historic site in April 1973. The Cordon of Chungmu of the Order of Military Merit, South Korea’s third highest military award, refers to his posthumous title. A festival is held each April at Chinhae, the headquarters of the Korean Navy, which celebrates blossoming cherry trees and honors Admiral Yi Sun-shin. A large statue of Yi Sun-shin graces the grounds of the Korean Naval Academy, while an even larger statue rises in the middle of Sejongno in downtown Seoul: there is no more prominent urban monument in Asia. Replicas of the Turtle ship have been constructed: one serves as the centerpiece of Korea’s National Museum, while another currently graces the harbor at Yosu.

The judgment of Admiral Yi Sun-shin’s peers underscores his real as opposed to symbolic achievements. Japanese Admiral Heihachuro Togo held him in the highest regard. Togo’s victory of the Russian Baltic Fleet at Tsushima in 1905 changed the course of the histories of Japan, Russia and Korea, stimulated the rise of nationalism in many of Europe’s Asian colonies, secured Japan’s place as an imperial power and in these and many other ways altered the fabric of world history. Yet, when asked to measure his achievement against a similarly influential figure, Lord Nelson of Trafalgar, Togo remarked "You may wish to compare me with Lord Nelson, but do not compare me with Korea's Admiral Yi Sun-shin Sun-Sin . . . he is too remarkable for anyone." In 1921, British Admiral George Alexander Ballard also compared Yi Sun-shin to Lord Nelson:

It is always difficult for Englishmen to admit that Nelson ever had an equal in his profession, but if any man is entitled to be so regarded, it should be this great naval commander of Asiatic race who never knew defeat and died in the presence of the enemy; of whose movements a track-chart might be compiled from the wrecks of hundreds of Japanese ships with their valiant crews at the bottom of the sea, off the coasts of the Korean peninsula… and it seems, in truth, no exaggeration to assert that from first to last he never made a mistake, for his work was so complete under each variety of circumstances as to defy criticism… His whole career might be summarized by Yi Sun-shin’s remark that, although he had no lessons from past history to serve as a guide, he waged war on the sea as it should be waged if it is to produce definite results, and ended by making the supreme sacrifice of a defender of his country.7

Perhaps Yi Sun-shin’s most enduring personal legacy are the quotations commonly derived from his War Diary, or Nanjung Ilgi (see Sohn Pow Key (ed.), Nanjung Ilji: The War Diary of Admiral Yi Sunshin (Seoul: Yonsei University Press, 1977), that embody the values of a number of Asian traditions from Daoism to Zen Buddhism. Admiral Yi Sun-shin wrote that a warrior must master three roads, four obligations, five skills, and ten keys to security, along with three essentials, among other principles:

“The three roads are knowledge of the world; understanding of things as they are; and wisdom toward humanity.”

“The four obligations are to provide national security with minimal cost; to lead others unselfishly; to suffer adversity without fear; to offer solutions without blame.”

“The five skills are to be flexible without weakness; to be strong without arrogance; to be kind without vulnerability; to be trusting without naivete; and to have invincible courage.”

“The ten keys to security are purity of purpose, sound strategy, integrity, clarity, lack of covetousness, lack of addiction, a reserved tongue, assertiveness without aggression, being firm and fair, and patience.”
“The three essentials for the warrior are humility, discernment, and courage."
“Those who fight to live will die, those who fight to die will live.”

Study Questions:

  • 1. Compare Admiral Yi Sun-shin achievements with those of Sir Francis Drake and British Admiral Horatio Nelson. Yi Sun-shin’s ideas are rooted in Buddhist, Confucian and Daoist religious teachings and martial arts theory. Drake’s world view may be extracted from his last will and testament at It is far easier to explore and compare Admiral Nelson’s most famous quotations and examine the sources of his words and convictions, among which are “My character and good name are in my own keeping; Life with disgrace is dreadful. A glorious death is to be envied;” “Duty is the great business of a sea officer, all private considerations must give way to it, however painful it may be;” “recollect that you must be a seaman to be an officer and also that you cannot be a good officer without being a gentleman,” and “Something must be left to chance; nothing is sure in a sea fight above all”. A large list of the quotations of Admiral Nelson useful for purposes of comparison with Admiral Yi Sun-shin-list can be found at While making allowances for differences in time and in place, how do they men differ in outlook, source of inspiration and attitude towards others?
  • 2. Why, on broader grounds, do historians compare Admiral Yi Sun-shin to Sir Francis Drake and British Admiral Lord Nelson?
  • 3. What connections or parallels can be made between the life and service of Admiral Yi Sun-shin and other public figures in early modern or any other time in world history?
  • 4. What aspects of Korean culture, including gender, emerge from a study of Yi Sun-shin’s life?
  • 5. To what degree was Yi Sun-shin an innovator in naval technology and strategy?
  • 6. What was the nature of Korea’s alliance with China? Why did it side with China against Japan?
  • 7. What role did China play in Korea’s war with Japan.
  • 8. How did Yi Sun-shin regard defeat and victory?
  • 9. How can Admiral Yi Sun-shin’s views on chivalrous conduct be compared to other warrior codes?
  • 10. Why did Toyatomi Hideyoshi invade Korea?
  • 11. What was the impact upon gender relations of the Imjin Wars, especially on male and female roles?
  • 12. Sites confidently repeating the problematic idea that the Turtle ships were ironclads or submarines include:
    Students can be assigned to speculate as historians do as to why such highly improbable “facts” are accepted in the absence of any real evidence.
  • 13. Examine the atrocities committed in Korea by Japanese forces in 1592 – 1598 and compare them to those inflicted on the Koreans by Japan in 1895 – 1945. Can you identify any patterns in these atrocities? Who and what are the chief targets and victims of these acts? Why? What did the Japanese do in 1994 that attempted to make amends for at least one of these acts? Were such practices or patterns repeated in Japanese activities in the Second World War towards Allied forces and European and Asian populations? How do the Japanese respond to charges that they have not adequately recognized or offered proper compensation for these acts, particularly towards Koreans?
  • 14. Wartime atrocities are all too frequent in human history and quite common in Korean Japanese relations. How are these defined? Who defines them? What are some examples of “atrocities” in human history, from Carthage to My Lai? How do civilizations respond to charges that their behavior warrants the label of “atrocity?” Why do societies resist the label? Give examples.
  • 15. How did the politics of memory shape the way Admiral Yi Sun-shin is remembered? How does that compare with the memorialization of other world leaders, especially those whose reputations have been revised over time, such as Thomas Paine, Thomas Jefferson, Dwight D. Eisenhower, Captain Alfred Dreyfus, George Armstrong Custer or Shivaji (a recent biography of that Western Indian leader has been banned in Shivaji’s home province).



Ballard, George Alexander. The Influence of the Sea on the Political History of Japan. [Originally published in London: John Murray, 1921] reprinted Westport, Connecticut: Greenwood Press, 1972.

Covell, Jon Carter. Korea's Cultural Roots. Salt Lake City: Moth House, 3rd edition, 1981.

Cumings, Bruce. Korea’s Place in the Sun: A Modern History. New York, W. W. Norton. 1997.

Hunter, Ruth and Fritsch, Debra M. A Part of the Ribbon: A Time Travel Adventure Through the History of Korea. Newington, Connecticut: Turtle Press, 1997. Designed for young readers, it offers a journey through the evolution of Korean culture, language and customs as seen through the eyes of two children who learn Korean martial arts and calligraphy, and find themselves as participants the sea battles of the Turtle ships. By such literary devices, they engage the entire course of Korea’s history. It may be ordered by calling 1-800-778-8785.

Howe, Christopher. The Origins of Japanese Trade Supremacy, Development and Technology in Asia from 1540 to the Pacific War. Chicago: The University of Chicago Press, 1995.

Jho, Sung-do. Yi Sun-Shin: A National Hero of Korea. Chinhae, Korea: Choongmoo-kong Society Naval Academy, 1970.

Kim, Chung-jin. The Turtle Ship. New York: Random House, 2004. This is the
most recent work on the subject. Compare analysis and details with Underwood, below.

Lee, Chong-young (ed.). Imjin Changch'o: Admiral Yi Sun-shin's Memorials to Court. Seoul: Yonsei University Press, 1997. Yi Sun-shin’s own accounts of his battles, offering students the chance to examine historical documents which not only illuminate Yi Sun-shin’s battles, but also the political and social organization of early modern Korea. The work includes a biography of Yi Sun-shin by Yi Pun, his nephew.

Trumbull, Stephen. Fighting Ships of the Far East (2): Japan and Korea A. D. 612-1639. Botley, England: Osprey Press, 2003. Superb illustrations, including cutaway drawings.

Park, Yune-hee. Admiral Yi Sun-shin and His Turtleboat. Seoul, Korea: Shinsaeng Press, 1973.

Parker, Geoffrey. The Military Revolution; Military Innovation and the Rise of the West 1500-1800. Cambridge: Cambridge University Press, 2 ed., 1996.

Sohn, Pow Key (ed.). Ha Tae-hung, trans. Nanjung Ilji: The War Diary of Admiral Yi Sun-shin. Seoul: Yonsei University Press, 1977. Essentially Yi Sun-shin’s ships’ log, but reads like a memoir. This work also contains a chronology of Yi Sun-shin’s career and synopsis of his battles with superb battlefield maps. Available via Internet sites for as little as $8.00.

Yu, Songnyong. Choi Byonghyon, trans. The Book of Corrections: Reflections on the National Crisis during the Japanese Invasion of Korea, 1592-1598. Berkeley, California: Institute of East Asian Studies, 2003.

Yang, Sung-jin and Lee, Nam-hee. Click on the Click into the Hermit Kingdom. Seoul: Dongbang Media Co. Ltd, 2000.

Underwood, Horace H. Korean Boats and Ships. Seoul: Yonsei University Press, reprint of 1934 edition, 2000. Short but authoritative analysis of Turtle Ship construction and Korean ship-building. Offers an excellent bibliography of Korean sources on Admiral Yi Sun-shin and his times.