Admiral Yi Sun-shin

Admiral Yi Sun-shin 

(1545-1598)
In the annals of naval warfare, few commanders have achieved the near-mythical status of Admiral Yi Sun-shin, a Korean military genius whose tactical brilliance and unwavering loyalty transformed what seemed like certain defeat into one of history's most remarkable military victories. Born on April 28, 1545, in Seoul during the height of the Joseon Dynasty, Yi would rise from humble beginnings to become the architect of Korea's naval supremacy and the savior of his nation during its darkest hour.
Yi's early life was marked by both promise and struggle. Born into an aristocratic yangban family in Geoncheon-dong Street (present-day Inhyeon-dong, Jung-gu District), his family had traditionally served in civil rather than military positions. However, Yi's destiny lay on a different path. After marrying in 1564, he spent his adolescence and early adulthood in Asan, where his mother's relatives lived and where a shrine to his memory now stands. From childhood, Yi displayed an unusual fascination with weapons and military strategy, though his parents initially hoped he would follow the family tradition of scholarly service.
Yi's military career began with characteristic determination and resilience. In 1566, he decided to pursue military service and began studying military science. His first attempt at the military examination in 1572 ended in dramatic fashion when he broke his leg during the test. Witnesses were astonished to see the young candidate calmly bind his broken leg with a willow branch before quietly continuing. This display of stoic resolve would become a defining characteristic throughout his life. Four years later, at age 32, Yi finally passed the military service examination in 1576.
Yi's early military career was marked by both competence and controversy. His unwillingness to compromise his integrity often put him at odds with corrupt officials and jealous colleagues. He served at various army and navy posts, including a challenging assignment as acting commandant of Konwon fortress on Korea's troubled northern frontier, where he successfully defeated Manchurian (Jurchen) forces by luring them into a trap and capturing their leader. However, his principled stance cost him dearly – he was twice discharged after being falsely accused by envious colleagues and even demoted to common foot soldier due to false accusations by another officer who blamed Yi for his own mistakes.
One revealing anecdote from his early career illustrates Yi's moral character. After passing the military examination, Minister of War Kim Kwiyŏng wanted to make Yi his son-in-law by offering him his daughter, born of his concubine. Yi refused, explaining, "I have just entered the government service. How can I dare seek promotion by making a connection with a powerful family?" This principled refusal to curry favor with powerful families would define his approach to service throughout his career.
Yi's personal philosophy was encapsulated in his own words: "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". This stoic worldview would sustain him through the incredible challenges ahead.
The transformation of Korean naval warfare began in earnest when Yi received an exceptional promotion to Commander of Cholla Left Naval Station in 1591, just months before the outbreak of war. This appointment came through the vigorous recommendation of Prime Minister Yu Song-nyong, who had known Yi since childhood and firmly believed that Korea needed his abilities. Yi immediately set about revolutionizing Korean naval capabilities, focusing on training his men, stocking equipment and supplies, and developing what would become his most famous innovation.
Yi's genius lay not in inventing the turtle ship from scratch, but in perfecting and deploying an existing concept with devastating effectiveness. The geobukseon (turtle ship) had existed in various forms since the 15th century during the reigns of King Taejong and Sejong. However, Yi's improvements transformed it into a revolutionary weapon of war. His turtle ships featured a completely enclosed deck covered with iron-bound, four-inch thick wooden planking that was virtually impervious to enemy fire. The upper deck was studded with spikes and knives to discourage enemy boarding attempts.
The most iconic feature was the dragon-headed prow, which could emit smoke or fire cannons, creating both psychological terror and tactical advantage. Yi apparently invented the "smokescreen," an on-board smoke generator using sulfur and saltpeter that created "a mist so that the enemy cannot see the ship". The vessels were armed with cannons that could fire from multiple directions – the dragon's mouth, stern, and sides – giving them unprecedented offensive capabilities. These technological innovations, combined with Yi's tactical genius, would prove decisive in the coming conflict.
The Japanese invasion of 1592 marked the beginning of what Koreans call the Imjin War and what history remembers as one of Asia's most consequential conflicts. Toyotomi Hideyoshi's ambitious plan to conquer Korea as a stepping stone to invading Ming China initially met with stunning success on land. Over 24,000 Japanese troops landed at Busan in May 1592, followed by reinforcements that swelled their numbers to over 150,000 men armed with advanced gunpowder weapons. The Japanese forces, largely composed of battle-hardened veterans, swept northward with lightning speed, capturing Seoul in just nineteen days and continuing on to Pyongyang.
However, Hideyoshi had fatally underestimated the importance of naval supremacy and the capabilities of Korea's new naval commander. Yi had received news of the invasion on May 25th, along with the shocking intelligence that both Gyeongsang naval commands had already self-destructed. Rather than panic, Yi waited patiently, confident that the Japanese could be defeated at sea despite their land superiority. His strategy was simple but brilliant: cut Japanese supply lines and prevent naval reinforcement of their land forces.
Yi's first naval victories established a pattern that would define the entire war. On June 16, 1592, Yi led a combined fleet with Admiral Yi Eok-gi and the notoriously difficult Admiral Won Gyun in what became known as the Battle of Okpo. With 24 panokseons, 15 auxiliary ships, and 46 boats, Yi engaged over 50 Japanese ships at anchor near Okpo harbor. The Japanese, caught while plundering the port, rushed to their ships as the Korean fleet approached. Yi spread his fleet in an enveloping formation and used his ships' superior cannon range to prevent the Japanese from employing their preferred boarding tactics. Twenty-six Japanese ships were destroyed on the first day, with eleven more eliminated the following morning. The Korean fleet suffered minimal losses.
Four days later, at Sacheon, Yi again demonstrated his tactical brilliance. His turtle ships, deployed in the vanguard, struck directly at the Japanese flagship while Korean archers targeted enemy commanders. The spectacle and ferocity of the turtle ships caused enemy vessels to scatter in confusion, resulting in another decisive Korean victory. The Battle of Tangp'o three days later followed the same pattern – turtle ships in the van, targeting enemy leadership, and devastating cannon fire from multiple directions.
These early victories revealed Yi's revolutionary approach to naval warfare. He developed the "crane wing" or "stork's wing" formation – a line abreast with flanks slightly advanced – that maximized his ships' firepower while maintaining tactical flexibility. His "holding onto each other's tail" protocol enabled each ship to bring maximum firepower to bear on targets in sequence. Perhaps most innovative was his "drawing the fish into the net" tactic – feigning retreat to lure entire enemy fleets into predetermined killing zones.
The Battle of Hansan Island on August 14, 1592, showcased Yi's tactical genius at its peak. Using his crane wing formation with turtle ships leading the charge, Yi's fleet decimated a massive Japanese armada. The combination of superior Korean gunnery, innovative ship design, and brilliant tactical deployment resulted in one of the most lopsided naval victories in history. Japanese survivors described the turtle ships as "sea monsters" that breathed fire and smoke while crushing their wooden vessels.
Yi's success stemmed from understanding a fundamental principle of naval warfare that he articulated clearly: "No invader from the sea can obtain final victory unless he can completely control the sea". By systematically destroying Japanese naval forces and supply convoys, Yi effectively starved the Japanese land forces of reinforcements and provisions. This strategic insight proved prophetic – the Japanese army, initially successful on land, was eventually forced to retreat southward due to severed supply lines.
Political intrigue and false imprisonment nearly ended Yi's career at the height of his success. In 1597, a complex conspiracy involving the Japanese double agent Yoshira and domestic political rivals led to Yi's downfall. The plot began when Yoshira provided intelligence suggesting that Japanese General Katō Kiyomasa would attack with a great fleet at a specific location. General Kim Gyeong-seo convinced Field Marshal Gwon Yul and ultimately King Seonjo to order Yi to launch an ambush.
Yi refused the order, recognizing that the indicated location was "studded with sunken rocks" and "extremely dangerous" for naval operations. More importantly, he suspected a trap. When Yi's refusal reached the court, his enemies, led by the Soin faction supporting Won Gyun, quickly moved against him. Yi was arrested, brought to Seoul in chains, and subjected to torture including whipping, flogging, burning, and having his legs broken. Only the intervention of his supporters at court, who convinced the king of Yi's past services, saved him from execution.
The psychological toll of this betrayal was immense. During his imprisonment, Yi's elderly mother in Asan was so shocked and heartbroken by news of her son's disgrace that she died. Yi, stripped of his rank and reduced to serving as a common foot soldier under General Kwon Yul, had to endure the ultimate humiliation while his country faced mortal danger. On his way to his new assignment, he stopped in Asan to mourn his mother's death, wearing sackcloth in accordance with Korean tradition. The sight of the great admiral reduced to such circumstances moved the local population to tears.
Won Gyun's catastrophic defeat vindicated Yi's strategic wisdom while nearly destroying Korean naval power. Appointed as Yi's replacement, Won Gyun proved "far inferior to Yi in his direction of naval affairs and lazy in the duties of managing the sailors and the fleet". When Yoshira returned urging immediate action against the approaching Japanese fleet, Won Gyun marshaled every available ship – 134 warships representing virtually the entire Korean navy – and sailed into the trap Yi had warned against.
The Battle of Chilchonryang became Korea's sole naval defeat of the entire war, but its consequences were catastrophic. Won Gyun's "inept and clumsy maneuvers" led to panic among his forces. When the battle turned against him, Won Gyun fled to land, only to be beheaded by a waiting Japanese soldier. Of the 134 Korean warships, only 12 managed to escape under Commander Pae Sŏl.
The miraculous reinstatement and the Battle of Myeongnyang represent perhaps the most dramatic reversal in military history. Faced with naval annihilation, King Seonjo hastily reinstated Yi as Supreme Naval Commander. Yi, despite his recent humiliation and personal grief, immediately accepted the responsibility. His first assessment was sobering – he had only 13 ships (including one additional vessel acquired after his return) and initially just 120 men, though survivors of Chilchonryang gradually rallied to him.
King Seonjo, convinced that the Korean navy was finished, sent orders to disband the remaining naval forces and incorporate them into the army under General Kwon Yul. Yi's response became legendary: "Your majesty, this vassal still has twelve battleships. Even though our navy is small, as long as I live the enemy will not dare to look down on us". This declaration of defiance in the face of impossible odds exemplified Yi's unbreakable spirit.
The Battle of Myeongnyang on October 26, 1597, stands as one of the most extraordinary military achievements in human history. Yi positioned his tiny fleet of 13 ships in the treacherous Myeongnyang Strait, known for its powerful tidal currents and hidden rocks. Against him came a Japanese armada of at least 133 ships, though some sources suggest the enemy fleet numbered over 300 vessels. The mathematical impossibility of victory – outnumbered more than 10 to 1 – was compounded by the Japanese forces' confidence and experience.
Yi's tactical brilliance turned natural obstacles into advantages. He positioned his flagship as bait, luring the Japanese vanguard into the narrow strait where their superior numbers became a liability. The powerful tides that made the strait dangerous for most vessels became Yi's ally – he had intimate knowledge of the currents and timing. As Japanese ships crowded into the confined waters, they became perfect targets for Korean cannon fire while being unable to maneuver effectively.
The battle's turning point came when Yi's flagship, despite taking heavy damage, held its position against overwhelming odds. This inspired his other commanders – first magistrate An Wi, then central squadron leader Kim Ŭngham, and finally the entire Korean fleet joined the desperate fight. As the tide shifted, Japanese ships began drifting backward and colliding with each other in the narrow strait. Yi ordered his ships to advance and press the attack, ramming and destroying 31 Japanese vessels while losing none of his own.
The aftermath was equally devastating for the Japanese. The strong currents prevented sailors from swimming to shore, causing many to drown. The psychological impact was enormous – the "invincible" Japanese navy had been humiliated by a handful of Korean ships commanded by a man they had believed was finished. This victory effectively ended Japanese hopes of securing their supply lines and forced their land armies to begin withdrawing from northern Korea.
The final campaign and heroic death at the Battle of Noryang demonstrated Yi's continued tactical excellence even as his own life drew to its close. In 1598, with Toyotomi Hideyoshi's death, Japan ordered the withdrawal of its forces from Korea. However, Yi was determined that the Japanese evacuation would not be peaceful. Working closely with Chinese Admiral Chen Lin, he planned to intercept and destroy the retreating Japanese fleets.
On December 16, 1598, Yi led a combined allied force of about 150 Korean and Chinese ships against over 500 Japanese vessels commanded by Shimazu Yoshihiro. The battle raged from early morning past dawn, with Yi's forces systematically destroying or capturing more than half of the Japanese fleet. In a cruel twist of fate, as victory became certain, a stray arquebus bullet from a Japanese ship struck Yi near his left armpit.
Sensing that the wound was fatal, Yi demonstrated his characteristic selflessness in his final moments. His last words, witnessed only by his eldest son Yi Hoe, adjutant Song Hui-rip, and nephew Yi Wan, were: "We are about to win the war – keep beating the war drums. Do not announce my death". Understanding that news of his death could demoralize the fleet at the moment of victory, Yi ordered his identity concealed until the battle was complete.
Yi Wan, displaying the same courage that ran in the family, donned his uncle's armor and continued beating the war drum to maintain the illusion that the admiral still commanded. When Chinese Admiral Chen Lin's ship found itself in trouble and Yi's flagship came to the rescue, Chen called out to thank Yi for the assistance. Instead, he was met by Yi Wan's heartbreaking announcement of his uncle's death. It is recorded that Chen was so shocked he "fell to the ground three times, beating his chest and crying".
The personal cost of genius emerges clearly from Yi's own writings and the accounts of those who knew him. His War Diary (Nanjung Ilgi), now recognized by UNESCO as part of the Memory of the World registry, reveals a man of profound depth and humanity. Written in elegant cursive Chinese script on traditional mulberry paper, the diary covers seven years of war from January 1592 through November 1598, ending just days before his death.
The diary reveals Yi not just as a military commander but as a complete human being grappling with the enormous burdens of leadership. He wrote about the strict discipline of military life, his thoughts on political affairs, descriptions of individual combat and overall war strategy, expressions of loyalty to country, worries about the common people, filial devotion, and miscellaneous personal affairs. The style is "simple and elegant," reflecting a man who sought clarity in all things.
Yi's responsibilities extended far beyond commanding battles. He was personally responsible for provisions, military supplies, distribution, recruitment, care for the wounded, shipbuilding, manufacture of cannons and ammunition, farming, and even salt production to raise funds. The government, rather than supporting him, occasionally demanded that he send supplies of paper and weapons to the Royal Court from his own resources. He managed these overwhelming logistics while facing constant political interference from court factions more interested in personal advancement than national survival.
The dimensions of Yi's achievement become clear when viewed against the broader context of 16th-century warfare. His tactical innovations influenced naval strategy far beyond Korea's borders. The turtle ship design principles – armored protection, multi-directional firepower, psychological warfare elements – presaged developments in naval architecture by centuries. His formation tactics, particularly the crane wing and coordinated fleet movements, were studied and adopted by naval academies worldwide, including those of the United States, United Kingdom, and Japan.
Perhaps most remarkably, Yi achieved this revolutionary impact despite having no formal naval training before the war began. Military historians have placed him "on par with Admiral Horatio Nelson as arguably the greatest naval commander in history" based on his undefeated record against seemingly insurmountable odds. His string of 23 consecutive victories, many achieved while vastly outnumbered and undersupplied, remains unmatched in naval history.
Modern Korean reverence for Yi Sun-shin reflects his enduring significance to Korean identity and values. His statue dominates Gwanghwamun Square in central Seoul, standing 17 meters tall and depicting the admiral holding his sword with a miniature turtle ship at the base. The surrounding 12:23 Fountain commemorates his 23 battles fought with his 12 remaining ships after the Chilchonryang disaster. The statue, erected in 1968, was deliberately placed at President Park Chung-hee's direction at the Sejong-no intersection as a symbol of Korean strength and determination.
Yi's image graces the 100-won coin, ensuring that millions of Koreans encounter his likeness daily. His hometown of Asan maintains Hyeonchungsa, a memorial shrine that houses his war diary and other personal belongings under the oversight of Korea's Cultural Heritage Administration. The diary, designated as National Treasure #76, was so revered that during the Japanese colonial period, Yi's descendants refused the Japanese imperial family's request to take possession of it.
Contemporary business and military applications of Yi's leadership principles demonstrate his enduring relevance. Korean business leaders regularly cite his philosophies, particularly his famous maxim: "Those willing to die will live, and those willing to live will die". Samsung Electronics President Hwang Chang-Gyu adopted this saying as his business philosophy, while former Agriculture Minister Jeong Un-Cheon used Yi's principles to overcome Korea's economic crisis. Korean telecommunications giant KTF teaches Yi's "dauntless venture spirit" to executives, and numerous universities offer Yi Sun-sin leadership courses.
The international recognition of Yi's genius extends well beyond Korea's borders. His battle tactics are taught in naval academies worldwide, and military historians consistently rank him among history's greatest commanders. The Russo-Japanese War of 1904-1905, which altered the balance of power in Asia, was won by Japanese forces that had finally learned and adopted Yi's innovative naval strategies. This historical irony – that Japan's later naval supremacy was built on principles developed by the Korean admiral who had defeated them – speaks to the enduring value of Yi's innovations.
The turtle ship's legacy in military technology cannot be overstated. Often regarded as the world's first ironclad warship, it preceded similar developments in Western navies by centuries. The psychological warfare elements – the dragon head emitting smoke and fire, the intimidating appearance, the apparent invulnerability – became standard features of later armored vessels. Modern naval architects studying the design marvel at its integration of offensive capabilities, defensive protection, and psychological impact into a single platform.
Admiral Yi Sun-shin died as he had lived – in service to his country and his principles. His death at age 53, just as Korea achieved final victory over its invaders, represents both tragedy and triumph. He never lived to see the peace his sacrifices had secured, never received the full recognition he deserved from the government he had saved. Yet his legacy transcends his mortal limitations. In Asan, he was buried next to his father according to Korean tradition, and the court posthumously awarded him the rank of Minister of the Right and the title Chungmugong – "Duke of Loyalty and Warfare".
The man who had declared himself unbreakable – "I can be approached, but never pushed; befriended but never coerced; killed but never shamed" – had proven his words through a lifetime of extraordinary service. His war diary, his tactical innovations, his undefeated record, and above all his unwavering loyalty to Korea despite repeated betrayals, established him as more than a military commander. He became the embodiment of Korean resilience, the proof that superior character and brilliant strategy could triumph over overwhelming material disadvantages.
Today, as visitors stand before his statue in Gwanghwamun Square or read his diary entries preserved by UNESCO, they encounter not just a historical figure but an enduring inspiration. Admiral Yi Sun-shin's life demonstrated that individual excellence, moral courage, and strategic brilliance could indeed change the course of history. His legacy reminds us that in humanity's darkest hours, extraordinary individuals can emerge to light the way forward, leaving behind examples that inspire and guide future generations long after their earthly battles have ended.