Yi Sun Shin, Korea's Great Admiral

The 16th-Century Naval Commander Is Still Revered Today

Low Angle View Of Admiral Yi Sun-Shin Statue In City Against Sky
Min A Lee / EyeEm / Getty Images

Admiral Yi Sun Shin of Joseon Korea is revered today in both North Korea and South Korea. Indeed, attitudes toward the great naval commander verge on worshipful in South Korea, and Yi appears in several television dramas, including the eponymous "Immortal Admiral Yi Sun-shin" from 2004-05.  The admiral almost single-handedly saved Korea during the Imjin War (1592-1598), but his career path in the corrupt Joseon military was anything but smooth.

Early Life

Yi Sun Shin was born in Seoul on April 28, 1545. His family was noble, but his grandfather had been purged from the government in the Third Literati Purge of 1519, so the Deoksu Yi clan steered clear of government service. As a child, Yi reportedly played commander in neighborhood war games and made his own functional bows and arrows. He also studied Chinese characters and classics, as was expected of a yangban boy.

In his twenties, Yi began to study at a military academy. There he learned archery, horseback riding, and other martial skills. He took the Kwago National Military Exam to become a junior officer at the age of 28, but fell from his horse during the cavalry test and broke his leg. Legend holds that he hobbled to a willow tree, cut some branches, and splinted his own leg so that he could continue the test. In any case, he failed the exam due to this injury.

Four years later, in 1576, Yi took the military exam once more and passed. He became the oldest junior officer in the Joseon military at the age of 32. The new officer was posted to the northern border, where Joseon troops regularly battled Jurchen (Manchu) invaders.

Army Career

Soon, young officer Yi became known throughout the army for his leadership and his strategic mastery.  He captured the Jurchen chief Mu Pai Nai in battle in 1583, dealing the invaders a crushing blow. In the corrupt Joseon army, however, Yi's early successes led his superior officers to fear for their own positions, so they decided to sabotage his career. Conspirators led by General Yi Il falsely accused Yi Sun Shin of desertion during a battle; he was arrested, stripped of his rank, and tortured.

When Yi got out of prison, he immediately re-enlisted in the army as an ordinary foot-soldier. Once again his strategic brilliance and military expertise soon got him promoted to commander of a military training center in Seoul, and later to military magistrate of a rural county. Yi Sun Shin continued to ruffle feathers, however, refusing to promote the friends and relatives of his superiors if they did not merit a higher position.

This uncompromising integrity was very unusual in the Joseon army and made him few friends.  However, his value as an officer and strategist kept him from being purged.

Navy Man

At the age of 45, Yi Sun Shin was promoted to the rank of Commanding Admiral of the Southwestern Sea, in the Jeolla region, despite the fact that he had no naval training or experience.  It was 1590, and Admiral Yi was acutely aware of the growing threat posed to Korea by Japan.

Japan's taiko, Toyotomi Hideyoshi, was determined to conquer Korea as a stepping stone to Ming China. From there, he even dreamed of expanding the Japanese Empire into India. Admiral Yi's new naval command lay in a key position along Japan's sea route to Seoul, the Joseon capital.

Yi immediately began to build up the Korean navy in the southwest, and ordered the construction of the world's first iron-clad, the "turtle ship." He stockpiled food and military supplies and instituted a strict new training regimen. Yi's command was the only section of the Joseon military actively preparing for war with Japan.

Japan Invades

In 1592, Hideyoshi ordered his samurai army to attack Korea, beginning with Busan, on the southeast coast. Admiral Yi's fleet sailed out to oppose their landing, and despite his complete lack of naval combat experience, he quickly defeated the Japanese at the Battle of Okpo, where he was outnumbered 54 ships to 70; the Battle of Sacheon, which was the debut of the turtle boat and resulted in every Japanese ship in the fight sinking; and several others.

Hideyoshi, impatient at this delay, deployed all 1,700 of his available ships to Korea, meaning to crush Yi's fleet and take control of the seas. Admiral Yi, however, responded in August 1592 with the Battle of Hansan-do, in which his 56 ships defeated a Japanese detachment of 73, sinking 47 of Hideyoshi's ships without losing a single Korean one. In disgust, Hideyoshi recalled his entire fleet.

In 1593, the Joseon king promoted Admiral Yi to the commander of three provinces' navies: Jeolla, Gyeongsang, and Chungcheong. His title was Naval Commander of the Three Provinces. Meanwhile, however, the Japanese plotted to get Yi out of the way so that the Japanese army's supply lines would be secure. They sent a double agent called Yoshira to the Joseon Court, where he told Korean General Kim Gyeong-seo that he wanted to spy on the Japanese. The general accepted his offer, and Yoshira began feeding the Koreans minor intelligence. Finally, he told the general that a Japanese fleet was approaching, and Admiral Yi needed to sail to a certain area to intercept and ambush them.

Admiral Yi knew that the supposed ambush was actually a trap for the Korean fleet, laid by the Japanese double agent. The area for the ambush had rough waters that hid many rocks and shoals. Admiral Yi refused to take the bait. 

In 1597, because of his refusal to sail into the trap, Yi was arrested and tortured almost to death.  The king ordered him executed, but some of the admiral's supporters managed to get the sentence commuted. General Won Gyun was appointed to head the navy in his place; Yi once more was broken down to the rank of foot-soldier.

Meanwhile, Hideyoshi launched his second invasion of Korea early in 1597. He sent 1,000 ships carrying 140,000 men. This time, however, Ming China sent the Koreans thousands of reinforcements, and they managed to hold off the land-based troops. However, Admiral Yi's replacement, Won Gyun, made a series of tactical blunders at sea that left the Japanese fleet in a much stronger position.

On August 28, 1597, his Joseon fleet of 150 warships blundered into a Japanese fleet of between 500 and 1,000 ships. Only 13 of the Korean ships survived; Won Gyun was killed. The fleet that Admiral Yi had so carefully built was demolished. When King Seonjo heard about the disastrous Battle of Chilchonryang, he immediately reinstated Admiral Yi -- but the great admiral's fleet had been destroyed.

Nonetheless, Yi was defiant of orders to take his sailors ashore. "I still have twelve warships under my command, and I am alive. The enemy shall never be safe in the Western Sea!" In October of 1597, he lured a Japanese fleet of 333 into the Myeongnyang Strait, which was narrow and dredged by a powerful current. Yi laid chains across the mouth of the strait, trapping the Japanese ships inside. As the ships sailed through the strait in a heavy fog, many hit rocks and sank. Those that survived were enveloped by Admiral Yi's carefully deposed force of 13, which sank 33 of them without using a single Korean ship.  The Japanese commander Kurushima Michifusa was killed in action.

Admiral Yi's victory at the Battle of Myeongnyang was one of the greatest naval triumphs not just in Korean history, but in all of history. It thoroughly demoralized the Japanese fleet and cut the supply lines to the Japanese army in Korea.

The Final Battle

In December of 1598, the Japanese decided to break through the Joseon sea blockade and bring the troops home to Japan. On the morning of December 16, a Japanese fleet of 500 met Yi's combined Joseon and Ming fleet of 150 at Noryang Strait. Once again, the Koreans prevailed, sinking about 200 of the Japanese ships and capturing an additional 100. However, as the surviving Japanese retreated, a lucky arquebus shot by one of the Japanese troops hit Admiral Yi in the left side.

Yi feared that his death could demoralize the Korean and Chinese troops, so he told his son and nephew "We are about to win the war. Do not announce my death!" The younger men carried his body below decks to conceal the tragedy and re-entered the fight.

This drubbing at the Battle of Noryang was the last straw for the Japanese. They sued for peace and withdrew all troops from Korea. The Joseon kingdom, however, had lost its greatest admiral.

In the final tally, Admiral Yi was undefeated in at least 23 naval battles, despite being seriously outnumbered in most of them. Although he had never fought at sea before Hideyoshi's invasion, his strategic brilliance saved Korea from being conquered by Japan. Admiral Yi Sun Shin died defending a nation that had betrayed him more than once, and for that, he is still honored today throughout the Korean Peninsula and is even respected in Japan.

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Szczepanski, Kallie. "Yi Sun Shin, Korea's Great Admiral." ThoughtCo, Aug. 27, 2020, thoughtco.com/admiral-yi-sun-shin-3896551. Szczepanski, Kallie. (2020, August 27). Yi Sun Shin, Korea's Great Admiral. Retrieved from https://www.thoughtco.com/admiral-yi-sun-shin-3896551 Szczepanski, Kallie. "Yi Sun Shin, Korea's Great Admiral." ThoughtCo. https://www.thoughtco.com/admiral-yi-sun-shin-3896551 (accessed March 23, 2023).

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