ADMIRAL YI SUN-SHIN AND THE KOREAN TURTLE BOAT
The Korean Turtle Boat is a prominent exhibit in our Museum and draws much comment. The well presented summary which accompanies it gives a brief account of the role of the turtle boat, and that of its commander Admiral Yi Sun-shin, during the Korean-Japanese wars of 1592 to 1599. The article which follows below presents some further detail concerning the development of the turtle boat, together with the life and career of Admiral Yi. The principal reference is the book “Yi Sun-shin, A National Hero of Korea” by Jho Sung-do, published in 1970 by the Choongmoo-kong Society. In addition there is a detailed account of Admiral Yi’s life and career on the Wikipedia website, under “Admiral Yi Sun-sin”.
Admiral Yi was born in Seoul, Korea, on the 25th of April, 1545, to parents of modest means. At this point in history Portuguese explorers had made their way to the East Indies and Japan, seeking to colonize and trade. Their arrival added to the already well-developed culture of broad-ranging trade and commerce that existed in this part of the world, extending as far as India and Persia. However China, as we know, had elected to eliminate its maritime dominance in 1423. It was no longer a maritime power.
As a student Yi was conscientious and capable, developing a broad understanding of the history and philosophy of his country. It was to be expected that when he completed his studies he would enter the ranks of officialdom, a preferred career path in those days in that part of the world. However, at the age of twenty two he surprised his parents by electing to pursue a military career – in the army. He developed skills in the martial arts of horsemanship and archery and in the study of military tactics, and at the age of thirty two passed the demanding examinations – both physical and academic – required in order to become an officer in the Korean army.
His first assignment was to a remote outpost on the northern border of Korea, where he remained for three years. Then, after short-term postings in Seoul and in the province of Chungchong, he was given command of the Bal-po naval base located in the province of Cheulla. Thus, for the first time, Yi Sun shin began to participate in navy life. He was thirty six years of age. However, at this point his career suffered a reversal. He refused to carry out an order from his commanding officer which he thought to be improper and he was returned to the staff position which he had occupied in Seoul. This represented both a demotion and a disgrace.
In January 1583, when Yi Sun-shin was thirty nine years old, he was assigned to the northern border of Korea where he had been before, this time to combat an invading force of Turchins. It turned out to be a long campaign, interrupted by a three-year period of mourning following the death of his father. He appears to have distinguished himself, he was wounded in the leg in one of the many skirmishes, and in due course, after the successful conclusion of the campaign, in 1589, he was re-assigned to Cheulla province. In February 1591 he took over command of the Cheulla Naval Station. This turned out to be the critical point of his career. It was critical also to the future of his country.
It had been obvious for some time that Japan had ambitions to attack and conquer Korea, and from there to invade China. Their timing was good. The Korean government had been for years the center of feuding between various factions, and both the military and the naval defenses had been allowed to decay. Admiral Yi recognized this, and immediately sought to re-establish discipline. More importantly, in contemplating the nature of the likely Japanese invasion fleet, he began to give consideration to the revival of the Korean turtle boat. He perceived, accurately as it turned out, that this heavily armored vessel, protected against boarders and armed with cannon, would out-gun and destroy the Japanese fleet, which was made up of small boats and men with muskets.
The turtle boat was not a new concept. From the beginning of the fourteenth century the Koreans had been developing various types of warships in order to discourage pirates It is believed that that the earliest version of the turtle boat may have been developed as early as 1413 AD. Admiral Yi’s interest came into focus in 1591 and he very quickly committed his resources to the building of a fleet of turtle boats – on a very limited budget. His action came in the nick of time.
The Japanese invasion came in April of 1592, just one year later. The Japanese forces were comprised of about 160,000 soldiers, 9,000 sailors, on board some 700 vessels. Their target was Pusan, a major port on the south coast of Korea. The Koreans were unprepared and the Japanese forces made rapid progress northwards from their established landing places. Admiral Yi, in the meantime, was marshalling, organizing and motivating his forces, in preparation for the counter-attack. It came on May 4th, 1592.
His fleet was comprised of 85 ships, of which 24 were turtle boats. The remainder was much smaller, but faster, scout boats and courier boats. It was the scout boats that sighted a substantial Japanese fleet at anchor in the port of Ohk-po, with the crews unprepared. The Koreans were able to attack and to destroy much of the Japanese fleet, while suffering minimal losses themselves. Perhaps more importantly it was a huge boost to the Korean morale. It was the first victory in what had been, to that point, a very one-sided war.
Following his victory at Ohk-po, Admiral Yi extended his search around the southern coast of Korea for the Japanese naval units operating there, and he found them. In a succession of actions, which became known as the Tang-po Naval Campaign, he and his fleet engaged and destroyed Japanese naval units at Sacheun, Tang-po, Tan-hang-po, and Youl-po.
This maritime campaign continued, and culminated in the battle of Hahnsan. This time however, there was a difference. Admiral Yi lured the Japanese fleet out from their anchorage and into open water. Here the turtle boat was able to exercise not only its impenetrability but also, using its oars, its maneuverability. The Historian H.G.Hulbert said, of the survivors:
“The few that escaped during the fight sped eastward toward home. So ended, we may well believe, one of the great naval battles of the world. It may truly be called the Salamis of Korea. It signed the death-warrant of the Japanese invasion, and it frustrated the great motive of the invasion, the humbling of China”.
Even though the Japanese had failed in achieving their principal objective the war dragged on. Peace talks were initiated in 1593 and they too dragged on until 1596, when hostilities were resumed. Then, in 1597, Admiral Yi through no fault of his own fell into huge disfavor. In Korea in those days, as in many other countries, intrigues and cabals played a major role in governance. In other words, the rulers were incompetent and corrupt. In this case the Japanese, perhaps during the peace negotiations, had gained the ear of senior Korean leaders, who were able to remove Admiral Yi from command of the Korean navy. Once again he was demoted and humiliated. With Admiral Yi out of the way, the Japanese rebuilt their navy and resumed their attacks on Korea. This time they were successful, and the Koreans suffered a series of defeats, both on land and at sea. Panic reigned. Admiral Yi was recalled, and as before he re-introduced discipline, reintroduced his successful tactics, and once again crushed the Japanese navy. Once more a series of successful naval engagements confirmed the superiority of the turtle boat and Admiral Yi’s discipline.
Then, on 19th• of November, 1598, in the battle of Noryang, a stray musket ball hit Admiral Yi below the left arm-pit. Like Nelson, he ordered that his face be covered so that his men would not know that he had been injured, and like Nelson he lived long enough to know that he and his men were the victors. The Japanese were finally and decisively beaten. It was a lasting lesson. Japan did not invade Korea again until 1910! Admiral Yi’s body was returned to Korea, to his home town Asan. He remains Korea’s great national hero.
Some technical considerations:
Admiral Yi described his proposed turtle boat as follows:
“The bow is equipped with a dragon’s head through which cannons are fired. The upper deck is covered by an armor plate to which sharp knives, spear heads and spikes are attached. The crew can sight the enemy and fire cannon through gun ports while remaining under the protection of the armored deck”. Some further description is offered in a book published in 1795, almost two hundred years after the admiral’s death. It notes that: “In the bow was the turtle’s head four feet three inches long by three feet wide. There a combination of sulfur and saltpeter was burned which emitted great clouds of smoke”.
Even in these brief, historical notes there are notable discrepancies. Obviously cannon and burning sulfur could not have been housed in the same turtle’s head at the same time. Neither could they have been enclosed in an opening four feet three inches long and three feet wide. However over the period of almost four hundred years through which the turtle boats operated, there would undoubtedly have been many modifications and variations. These factors need to be taken into account then we address our own museum turtle boat. We need to remember that over the years there were many versions.
Thus contemporary illustrations from the 1500’s show a narrow opening running the entire length of the hull from bow to stern. This was presumably for ventilation, which would have been necessary and in fact critical when the cannon were in action. There is no such provision in our model. There was also a slot on the deck, extending along most of its length. This was for accommodating the raising and lowering of the mast and sails. Also our model has a very tall “dragon’s head”, far taller than those shown on those earlier illustrations. It may be that this tall chimney did indeed have a fire at its foot, intended, we are told, to be the source of a smoke-screen. However the fire was more probably intended to generate an up-draft, which in turn would draw fresh air into the gun-ports, where it would be most needed. Without ventilation the gun-crews would have been asphyxiated. The generation of a smoke-screen was perhaps a secondary objective. However it was recorded that in battle the turtle boat had its sails lowered, and relied on its oars for maneuvering. This would have enabled them to at least evade their own smoke-screen, while the enemy would have been at the mercy of the wind.
It is also recorded that the turtle boats were “iron clad”, this to make them impenetrable to musket balls, and resistant to flaming arrows. In fact it is claimed that these were the first “iron clad” warships. Admiral Yi himself noted that the deck was iron clad but he makes no mention of the hull. Thus the turtle boats probably were iron clad in some way, but there is no sign of it on our model.
References:
Yi Sun-shin. A national Hero of Korea. By Jho Sung-do. First edition 1970.
Wikipedia: Admiral Yi Sun-sin.
Edited by: Peter Davies 2011
In addition to the well written article by Peter Davies, here are a few more insights into Admiral Yi Sun-sin and his role in Korean History:
There were numerous reasons why Yi was so successful against the Japanese fleets. Yi had prepared for the war by checking the status of his soldiers, granaries, and supplies, replacing them when it was necessary. As part of this preparation, Yi resurrected and built the turtle ship, which was a considerable factor in his victories. Yi also had a great deal of information about the southern Korean coast and he planned his battles using the sea tides and narrow straits to his advantage.
Yi was a charismatic leader, and was able to maintain his soldiers’ morale despite constantly being low on supplies and food, and continuous news of countless Korean losses in ground battles. In some records, it is stated that he went as far as to personally fulfill some of his soldiers’ dying wishes. He demonstrated his loyalty to the people by treating them with respect and fighting amongst them even when endangered. Because of this, Admiral Yi became immensely popular among his soldiers and the Korean people, who often provided him with intelligence reports at great risk to themselves.
The Joseon panokseon were structurally stronger than Japanese ships at the time. Panokseon had stronger hulls and could carry at least 20 cannons, compared to the Japanese 1 or 2. Japanese ship-mounted cannons were inferior to the Koreans’ in both range and power. Cannon development had been neglected by the Korean government, so Yi personally saw to it that the technology was developed. As such, the Korean side had several different types of cannons at their disposal in battle.
Admiral Yi was an excellent naval strategist. The Japanese navy’s strongest tactic was to board enemy ships and engage in hand-to-hand combat. The panokseon was slower than the Japanese ships so Yi had little room for error to negate the Japanese navy’s most dangerous tactic. He was able to do so in every naval engagement he commanded.
As Yi’s brilliance as a strategist revealed itself throughout the war, his legend grew. In what could be considered his greatest victory in the Battle of Myeongnyang, Yi proved victorious in the battle with 13 panokseon, while the Japanese had at least 333 ships (133 warships, at least 200 logistical). Yi also personally exercised command over his fleets, making the attack on Japanese ships coordinated and decisive.
It was largely due to Yi’s complete control of the seas that the Japanese were eventually forced to retreat, keeping Joseon safe from another Japanese invasion until the end of the war.
Joseon Government Reaction
Admiral Yi annihilated the Japanese invasion forces, while preserving and respecting his soldiers and their families. Yi was supported by many peasants for not only his victories, but his kindness and gratitude towards citizens affected by the war. They had much faith in Admiral Yi and he was regarded as more than just an admiral.[24] Nearly all awards to Admiral Yi and his deeds were awarded posthumously.[25]
On the other hand, King Seonjo had accomplished nothing to save his kingdom. At his greatest need, the Joseon Dynasty‘s king had failed to defend the kingdom and his rapid retreat to Uiju left his reputation in ruins. It is feasible to believe that King Seonjo and his royal court looked towards Admiral Yi’s victories and rising support as the foundations for a revolt.[26] King Seonjo, who feared that Admiral Yi may hold political power and instigate a revolt against him, arrested and tortured him. Defended by his loyal friend, Prime Minister Yu Seong-ryong, Admiral Yi was spared the death sentence twice.
Many royal advisors of the king played an important part in manipulating the king’s opinion of Admiral Yi. The Joseon government was plagued by factional fighting, jealousy, and hatred. The ministers feared and hated the successful admiral, while the royal court sulked in despair and ingratitude. Along with other jealous contemporaries, the sporadic conspiracies against Yi succeeded in restricting his true capabilities to completely destroy the Japanese invasion forces and supply routes.
It should also be noted that according to a recent Choson Ilbo article, historians have discovered written government recordings of the Joseon government’s reaction to Admiral Yi’s death. The records show that King Seonjo expressed a “blank expression”, offering no signs of sadness or shock.
Legacy of Admiral Yi Sun Sin
“Those willing to die will live, and those willing to live will die.” –Admiral Yi.
Today, Admiral Yi is considered one of Korea’s greatest heroes of all time. Koreans look upon Yi as a man of courage, perseverance, strength, self-sacrifice, intellect, and loyalty to his country.
Admiral George Alexander Ballard of the Royal Navy considered Yi a great naval commander, and compared him to Lord Nelson of England:
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 lying 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 saying 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. (The Influence of the Sea on The Political History of Japan, pp. 66–67.)
Admiral Togo regarded Admiral Yi as his superior. At a party held in his honor, Togo took exception to a speech comparing him to Lord Nelson and Yi Sun-sin.
It may be proper to compare me with Nelson, but not with Korea’s Yi Sun-sin, for he has no equal. (The Imjin War, by Samuel Hawley, pg. 490)
Prior to the 1905 Battle of Tsushima, Lieutenant Commander Kawada Isao recalled in his memoirs that:
…naturally we could not help but remind ourselves of Korea’s Yi Sun-sin, the world’s first sea commander, whose superlative personality, strategy, invention, commanding ability, intelligence, and courage were all worthy of our admiration. (The Imjin War, by Samuel Hawley, pg. 490)
Admiral Tetsutaro Sato of the Imperial Japanese Navy mentioned the Korean admiral in his book published in 1908:
Throughout history there have been few generals accomplished at the tactics of frontal attack, sudden attack, concentration and dilation. Napoleon, who mastered the art of conquering the part with the whole, can be held to have been such a general, and among admirals, two further tactical geniuses may be named: in the East, Yi Sun-sin of Korea, and in the West, Horatio Nelson of England. Undoubtedly, Yi is a supreme naval commander even on the basis of the limited literature of the Seven-Year War, and despite the fact that his bravery and brilliance are not known to the West, since he had the misfortune to be born in Joseon Dynasty. Anyone who can be compared to Yi should be better than Michiel de Ruyter from Netherlands. Nelson is far behind Yi in terms of personal character and integrity. Yi was the inventor of the covered warship known as the turtle ship. He was a truly great commander and a master of the naval tactics of three hundred years ago. (A Military History of the Empire (Japanese: 帝國國防史論), p. 399)
During the time of the invasion, it was up to the admiral to supply his fleet. Yi’s fleet was cut off from any helping hand from the king’s court and had to fend for itself. The admiral often wrote in his war diary, Nanjung Ilgi War Diary of Admiral Yi Sun-sin, about how concerned he was about the food supply during winters. His enemy was fully supplied, and always outnumbered him.
Yi himself had never been trained as a naval commander. Korea, called Joseon at the time, did not have any naval training facilities. Although Yi passed the military exams when he was young, he was never trained at an academy. Yi’s only military experiences came from fighting foreign Jurchen tribes invading from Manchuria. In fact, the Battle of Okpo, his first victory against the Japanese fleet, was also his first sea battle ever. None of his subordinates, including his own staff, had ever fought at sea before.
One reason Admiral Yi was successful in his battles was because his cannon had longer range and power than the enemy’s, with the Japanese heavily favoring troop transport over naval combat. His turtle ship, which had first set sail the day before the invasion, was very effective in leading the attack and breaking the enemy’s formation. Yi won all of at least twenty-three naval battles fought while suffering very minimal losses, destroying over a thousand Japanese ships and killing tens of thousands of Japanese soldiers.
Admiral Yi used many different formations according to the situation, and capitalized on tides and ocean currents. Yi also took advantage of his knowledge of the surrounding sea. Many times, he lured the enemy to a place where his fleet would have the upper hand.
At the Battle of Hansando, the Japanese commander broke ranks and Yi routed his fleet. Yi’s expertise on naval strategy is apparent in the fact that his successor, Won Gyun, even with all of Yi’s ships and trained crew, could not defeat an enemy fleet of similar might. One of the greatest legacies of the admiral was the disruption of the Japanese supply line. Through his calculated attacks, he successfully burdened the Japanese navy and the supplies trying to reach their lines near the Chinese border.
Yi’s naval reforms did not persist and disappeared soon after his death. The turtle ships faded into the annals of Korean history, reaching iconic legendary status today. The Joseon royal court decided on a reduced military, especially after the Manchu invasions in the 1630s.
Yi kept a careful record of daily events in his diary, and it is from these entries, along with the reports he sent to the throne during the war, that much about him has been learned. Also, much information about the turtle ships are written in his diaries. These works have been published in English as Nanjung Ilgi: War Diary of Admiral Yi Sun-sin, and Imjin Jangcho: Admiral Yi Sun-sin’s Memorials to Court.
Among his direct male descendants, more than two hundred passed the military examination and pursued military careers, hence constituting a prominent family or military yangban of late Joseon. Although many of his male descendants did not play the kind of a vital role in the tumultuous factional politics of late Joseon, as did those of the Pyeongsan Shin and Neungseong Gu military yangban lines, the court seems to have treated them with respect. Many attained important high-level posts in the administration. Moreover, at the end of the Joseon Dynasty, at least several descendants are known to have become anti-Japanese independence activists. Today, most of Yi’s descendants live in or near Seoul and Asan.
In Korea, Admiral Yi is not only famous for the turtle ship, but also for his last words before his death. He told his nephew to wear his armor and to hide his death until the battle is over to avoid demoralizing his men in the middle of battle. His last words were, Do not let my death be known (나의 죽음을 알리지 마라).
Turtle Ship
One of Yi’s greatest accomplishments was resurrecting and improving the turtle ship (거북선, 龜船). With his creative mind and the support of his subordinates, Yi was able to devise the geobukseon, or Turtle Ship. Contrary to popular belief, the turtle ship was not actually invented by Admiral Yi; rather, he improved upon an older design that had been suggested during the reign of King Taejong.
The turtle ships designed by Yi held eleven cannons on each side of the ship, with two each at the stern and the bow. The ship’s figurehead was in the shape of a dragon. The figurehead itself held up to four cannons, and emitted a smokescreen that, in combination with its fierce appearance, was meant to be used as psychological warfare. The sides of the turtle ship were dotted with smaller holes from which arrows, guns, and mortars could be fired. The roof was covered with planks and spikes. The purpose of the spikes was to prevent the ship from being boarded by the enemy. The larger Japanese ships’ sides were higher than the turtle ships’ and thus, the spikes prevented boarders from jumping down onto the roof without risking impalement. There were two masts that held two large sails. The turtle ship was also steered and powered by twenty oars, which were pulled by two men during fair conditions and five in combat situations.
There is an ongoing debate as to whether the turtle ship had two decks or three; historians still have no definitive answer. Whichever is the case, it is clear that the turtle ship employed multiple decks to separate the rowers from the combat compartment. This enabled the turtle ship to be very mobile since wind and manpower could be used simultaneously. Most support the argument of two decks since that was what was drawn out in the first and second designs of the turtle ships. Some historians maintain that, since Yi was a unique individual and often pursued innovative ideas (contrary to the established wisdom of his peers), it is possible that he had the turtle ship built with three decks. It is known that his flag ship, a panokseon, had three decks during his campaigns, so there is support for the belief that the turtle ship had three decks.
Turtle ships are the most famous part of Admiral Yi’s fleet; however, he never deployed more than five in any one battle. The reason for this was not that the cost or construction time of the ship was prohibitive; rather, it was the naval strategy employed at the time. Unlike anywhere else in the world at the time (with the exception of England), the Joseon Dynasty used cannons as its primary offensive naval weapon. Historically, they had often used guns and cannons against Japanese pirates as early as the 1390s. The Joseon navy did not implement the ship-boarding strategy that the Japanese navy did, so it was imperative that their warships “stand off” from Japanese vessels. Admiral Yi made it a strategic priority to avoid hand-to-hand combat, in which the Japanese navy specialized. The turtle ship was developed to support his tactic against Japanese fleets.
Turtle ships were first used in the Battle of Sacheon (1592) and were used in nearly every battle until the devastating Battle of Chilchonryang, when a Japanese double-agent plot nearly succeeded, resulting in every turtle ship and all but 13 panokseon being sunk. The turtle ships did not re-appear in battle until the Battle of Noryang.
Turtle ships were mostly used to spearhead attacks. They were best used in tight areas and around islands rather than the open sea.
Reference: Wikipedia: Admiral Yi Sun-sin