Yi Sun-sin Fought 23 Naval Battles Against Japan and Never Lost One

He was tortured and demoted to a foot soldier by his own king, then reinstated with twelve ships to face a Japanese armada of at least 133 at Myeongnyang and won, and died in his final victory ordering his nephew to hide his death. His seven-year war diary is a UNESCO Memory of the World.

The cage

In the spring of 1597, the man who had not lost a naval battle in five years was dragged toward the capital in a cage on an ox cart, while people lined the road to watch and to protest the humiliation of their hero. Yi Sun-sin, commander of the Joseon navy, had been relieved of command, arrested, and taken to Seoul in chains to be imprisoned and tortured. The king wanted him dead. He was flogged, whipped, burned, and beaten with a cudgel until he was nearly dead, and he refused to confess to the false charges brought against him. A minister named Jeong Tak talked the king out of the execution; Yi's childhood friend, the chief councilor Yu Seong-ryong, who had carried him to high command, stayed silent through the deadly hour. The sentence was commuted to something a Joseon general considered worse than death: he was stripped of his rank and sent to fight as a common infantryman under General Gwon Yul.

Then his mother died. His father had died years before, in 1582. Now, in disgrace, barred from command, mourning, he broke. In his war diary, the Nanjung Ilgi, he wrote what he could not say to anyone: "O, what shall I do? Is there anyone else under heaven in such a pitiful plight as myself? The sooner I die the better." Another entry, in the Ha Tae-hung translation of the diary, records him dismounting at a friend's house and breaking into tears, then sitting "late at night all alone, as sadness incessantly swept over me."

This was not the first time his own government had done this to him. A decade earlier, early in his career on the northern frontier, superiors jealous of his success had falsely accused him of desertion in battle, and he had been stripped, imprisoned, and tortured then too, and refused to confess then too, and been demoted to the ranks then too, before a pardon in 1588 let him climb back. The pattern was already the shape of his life: the court would break him, and the war would call him back.

The war called him back now in the cruelest possible way. While Yi was afoot in the infantry, the navy he had built was handed to a rival, Won Kyun. Won Kyun was brave in a fight but drunken, undisciplined, and without strategic sense; Yi's diary had logged some thirty incidents of his misconduct in two years. Sailing the entire fleet, around 150 warships, toward Busan in August 1597, Won Kyun blundered into a Japanese force of 500 to 1,000 ships. On the night of August 28, in the strait of Chilcheollyang, the Japanese destroyed nearly the whole Joseon navy in a single engagement. Won Kyun fled ashore and was killed. Only a detachment of twelve warships under a subordinate, Pae Sol, who refused to join the slaughter and sailed away, survived. Every turtle ship Yi had built was lost. The sea, which Yi had held for five years, was suddenly Japan's.

When the court understood what had happened, it pardoned Yi and reinstated him as supreme commander of what was left. What was left was twelve ships, and roughly 120 sailors.

The twelve ships

The king, judging the navy beyond recovery, moved to dissolve it and fold its men into the land army. Yi answered with a memorial to the throne that is the most famous document he ever wrote. In it he argued that dissolving the navy would please the enemy and open the sea route up the Han River toward the capital, the outcome he feared most. The core of it, preserved in the classical Chinese in which he wrote it, was a single line of defiance: "This vassal still has twelve battleships," and, "Even though our navy is small, as long as I live the enemy will not dare to look down on us."

The court relented. He kept the navy.

This is the decision the whole life turns on. He had been tortured by the king he served, demoted to a foot soldier, and bereaved, and the empire he had defended had handed his fleet to the man who destroyed it. He could have walked away, and almost no one would have blamed him. Instead he took twelve ships and made them a navy again, because he understood something the court did not: that without command of the sea, the Japanese armies in the south could not be supplied, and the war would be lost on land even if it was won at sea. He had spent five years proving it. Now he would prove it with twelve ships.

To see why twelve ships could matter, you have to see what he had done before the cage. Yi Sun-sin was born in Seoul on April 28, 1545, into an aristocratic family whose fortunes had fallen; his grandfather had been purged from office, his father never served. He came to the military late and almost by accident, passing the military examination in 1576 at thirty-two, the oldest junior officer in his cohort, after falling from his horse in the cavalry test, breaking his leg, splinting it with a willow branch, and remounting to finish. The Joseon elite considered soldiering an inferior occupation. Yi chose it anyway, served against Jurchen raiders on the northern frontier, was wounded in the leg by an arrow and pulled it out himself so his men would not see their commander bleed, and kept being punished for refusing to ignore corruption.

In 1591 he was sent to the southern port of Yeosu as naval commander of Jeolla Left Province. He at once began to prepare for a war the court refused to believe was coming. He rebuilt ships, drilled gunners, and revived a half-forgotten Korean vessel, the turtle ship, the geobukseon, that had last been used generations before. The turtle ship was not his invention; records mention it as early as 1413. But he redesigned it for the coming enemy. In a memorial to the court after the battle of Sacheon, he described it in his own words: a ship "in the shape of a turtle," so that "our men can look out from inside, but the enemy cannot look in from outside," with a dragon's head at the bow "from whose mouth we could fire our cannons," and iron spikes on its back "to pierce the enemy's feet when they tried to board." It moved, he wrote, "so swiftly that it can plunge into the midst of even many hundreds of enemy vessels." There were probably never more than a dozen of them at any one time, and scholars still debate whether the deck was truly iron-plated or only spiked, but the point was never the armor. The point was speed and standoff gunfire: keep the world's best swordsmen at cannon range and never let them board.

When the Japanese invaded in the spring of 1592, Toyotomi Hideyoshi's armies tore north overland and took Seoul in nineteen days. At sea, it was different. Yi, who had never commanded a naval battle in his life, won his first engagement at Okpo, then Sacheon, then a string of others, using currents and narrow straits and the range of his cannon to deny the Japanese the boarding fight they wanted. On August 15, 1592, off Hansan Island, he lured the Japanese fleet out into open water with a decoy, then spread his ships in a crane-wing formation, a curved line with the turtle ships at the center, and destroyed roughly a hundred enemy vessels without losing a ship of his own. After Hansan, Hideyoshi forbade his admirals to fight the Korean navy at sea. Yi cut Japan's supply lines and held the sea for five years.

He fought, by the count most historians accept, twenty-three naval battles, and won all of them. In fourteen of them, not a single Japanese ship survived. He never lost a ship under his own command.

Then a Japanese plot exploited the factional paranoia at the Joseon court and engineered Yi's arrest. The court that would not believe the invasion was coming now believed a fabricated accusation against the one man who had stopped it, and the navy was given to Won Kyun, and the navy was destroyed, and Yi was in a cage. That is how he came to have twelve ships.

The strait

On the morning of October 26, 1597, Yi's scouts reported a Japanese fleet pouring toward him through the Myeongnyang Strait, off the southwest corner of Korea. He had thirteen ships, the twelve plus one pressed on him by local residents. The Japanese had at least 133 warships, and counting their support vessels, possibly more than 300. He was outnumbered by something like ten or twenty-five to one.

He had chosen the place with the same instinct he had used at Hansan, only now it was all he had. The Myeongnyang Strait was narrow, only a few hundred meters across, and its tidal currents ran fast and reversed direction every few hours, reaching speeds that could drag a ship sideways. Yi anchored his thirteen ships at the northern mouth of the strait, bows facing the channel, so that the Japanese had to come at him single file through a killing zone, and so that, if it went wrong, he still had a line of retreat. He was using the one advantage a smaller fleet always has: the enemy's own numbers become a trap in a confined space.

The Japanese came on with the tide. Then the tide turned. Their ships began to drift backward, to lose steerage, to collide with one another in the narrow water. Yi's fleet, holding formation, raked them with cannon. When the channel was choked with disabled and drifting hulls, he ordered the advance, and his ships rammed and sank thirty-one Japanese warships. The Japanese commander Kurushima Michifusa was killed; his body was pulled from the water and his head put on display to break the enemy's nerve. Yi lost no ships. He withdrew at nightfall, because even after the victory he was still hopelessly outnumbered and the wind was against him.

Myeongnyang is often called the greatest naval victory ever won against such odds. It did more than save the remnant navy. It cut the Japanese advance toward the capital from the sea, starved their land forces of resupply, and bought Korea the time to rebuild. The court had given him twelve ships and told him the navy was finished. He had made those twelve ships decide the war.

The last drum

The war lasted one more year. In late 1598, with Hideyoshi dead and the Japanese withdrawing, Yi joined the Ming Chinese admiral Chen Lin to intercept the retreating Japanese fleet of Shimazu Yoshihiro at the battle of Noryang, on the night of December 16, 1598. The allied force of about 150 Joseon and Ming ships caught the Japanese and destroyed or captured more than half of Shimazu's 500. As the Japanese broke and fled, Yi ordered a pursuit.

It was during the pursuit that a stray arquebus bullet from an enemy ship struck him near the left armpit. He knew the wound was fatal. The record, in the Ha Tae-hung translation of his war diary, gives the words he spoke to the two men at his side, his eldest son Yi Hoe and his nephew Yi Wan: "The war is at its height. Wear my armor and beat my war drums. Do not announce my death." He died moments later. Yi Wan put on his uncle's armor, and for the rest of the battle he stood on the flagship beating the drum so the fleet would not know its admiral was gone. When the Ming admiral Chen Lin later came to thank Yi for saving his ship in the fight, he was met by the nephew with the news, and the Chinese admiral is said to have fallen to the ground three times, beating his chest and weeping.

He had been hiding wounds from his men his whole life, since the day he pulled the arrow from his own leg on the northern frontier so no one would see. He did it one last time, from the grave.

He was fifty-three. He had kept the diary through all of it, almost daily, from January 1592 to days before he was killed, in seven volumes of simple, elegant classical Chinese. It records the battles and the tides and the weather, and also his grief, his fear, his loneliness, and the lives of the common people the war crushed. It is now National Treasure No. 76 of Korea and, since 2013, part of UNESCO's Memory of the World, described there as "without equal in world history as a commander's battlefield accounts." He wrote into it, among the tactics, a set of maxims for a warrior: the three essentials, he said, "are humility, discernment, and courage." The diary is the reason we have his despair in his own words, and his last order in his own voice.

After his death the honors came that had been withheld in life: the title Chungmu, Duke of Loyalty and Warfare; first-class military merit; and, eventually, the status of a national hero. The Japanese admiral Togo Heihachiro, who destroyed the Russian fleet at Tsushima in 1905, is said to have deflected a compliment by replying that next to Yi Sun-sin he was "little more than a petty officer." In Korea today his name is on towns, awards, streets, and warships. The cautionary half of the story is harder to memorialize: the navy was lost not by the enemy but by the court that removed its commander on a foreign spy's lie, and the miracle at Myeongnyang was necessary only because the men who should have trusted him did not.

Read the full life in his own words: Nanjung Ilgi: The War Diary of Admiral Yi Sun-sin, translated by Ha Tae-hung (Yonsei University Press, 1977), the UNESCO-listed primary source; for the surrounding war, Samuel Hawley's The Imjin War (Royal Asiatic Society / University of California, 2005) is the standard English history.