Yi Sun-sin
Also known as Chungmu 忠武 · 이순신 · 李舜臣
- Dates
- 1545–1598
- Era
- Joseon Korea; the Japanese invasions of 1592–1598
- Role
- Joseon admiral in the Imjin War
Yi Sun-sin held the sea against Japan's invasion of Korea, was sacked by his own court, and died winning the last battle of the war.
Who was Yi Sun-sin?
Yi Sun-sin was the Joseon naval commander who kept the sea during the Imjin War, Hideyoshi's invasions of Korea from 1592 to 1598. His name in hangul is 이순신, in hanja 李舜臣. After his death the court gave him the title Chungmu 忠武. He was not a lifelong favourite of King Seonjo. When the Japanese landed in 1592 he was Left Naval Commander of Jeolla. Through that summer and autumn he won a chain of battles, Hansando above all, that stopped the invasion fleet using the southern and western coasts as a road. Ming Chinese armies fought the land war with Joseon. His part was the supply line on the water.
Turtle ships, 거북선 (geobukseon), were covered warships with a spiked roof. He developed and used them. Joseon records mention the type in the previous century, and iron plating of the whole hull is disputed. Spikes and a closed deck are what his writings support. In 1597 court intrigue had him arrested, tortured, and demoted. His replacement lost the fleet at Chilcheollyang. Recalled with thirteen ships, he won at Myeongnyang, and he was killed at Noryang in 1598 as the Japanese withdrew after Hideyoshi's death. His war diary, the Nanjung ilgi 난중일기, was kept in classical Chinese during the war.
Key works
Nanjung ilgi 난중일기
His war diary, written in classical Chinese across the Imjin years, records weather, supply, discipline, and battle. It is a primary source, not a later patriotic novel, and his official reports sit beside it.
Key ideas
거북선
The turtle ship as a tool, not a marvel
A covered deck and iron spikes answered boarding, the Japanese fleet's habit. The ship was a designed weapon inside a line of battle, and the ironclad-submarine version is modern legend.
The strait decides the numbers
Myeongnyang is his clearest case: thirteen ships in a narrow channel, a reversing current, and a larger fleet that had to enter water he had chosen. Terrain and the hour did what a missing squadron could not.
Write it down under your own hand
The diary kept his version of orders, shortages, and the court's interference. A commander who will be slandered in the capital needs a record that is not the capital's record.
Famous episodes
Hansando
History1592
After early wins at Okpo and Sacheon, Yi brought the Japanese fleet to battle off Hansan island. Korean accounts give his formation the name crane wing, an arc that drew the enemy in and closed. The victory, with the battles around it, cost Japan control of the sea lane that should have fed the invasion. It is the offensive peak of his war.
Dismissal, then Myeongnyang
History1597
In 1597 a Japanese deception pushed the court to order an attack Yi judged suicidal. He refused, was arrested and nearly executed, and Won Gyun then lost the fleet at Chilcheollyang. Restored to a remnant he numbers at thirteen ships, he used the tide in the Myeongnyang strait to break a far larger force. The thirteen are his figure, and film totals for the enemy are not a source.
Noryang
History1598
Hideyoshi's death in 1598 removed the reason for the invasion, and as the Japanese left, a joint Joseon and Ming fleet caught them at Noryang. Yi was hit and died during the fight. Later biographies say he asked that his death be concealed until the battle was decided. The death in the battle is certain, and that last order is the tradition attached to it.
Myths vs facts
He invented an ironclad turtle ship centuries ahead of its time, and it won the war by itself.
He built and used covered turtle ships with spiked roofs in 1592, and earlier Joseon mentions of the type already exist. Full iron plating is disputed. The victories were fleet actions of seamanship and position, while Ming and Joseon armies fought the war on land.
The king trusted him throughout, as a grateful nation should.
In 1597 he was jailed, tortured, and reduced to the ranks. The fleet was then almost destroyed under another commander. The recall came after the disaster, not before it, and the diary is partly a record of that politics.
Myeongnyang was thirteen ships against a film number, won by courage alone.
Thirteen Joseon ships is the figure in his account, against a much larger Japanese fleet. The strait and the tidal current are the tactic. Exact enemy counts differ. A movie's number is a dramatisation.
Takeaways
- Learn the strait and the tide before you count the ships.
- Keep a record the court cannot quietly rewrite.
- Do not dismiss the one commander who can still fight that battle.
Rivals and connections
Sources
- Yi Sun-sin, Nanjung ilgi 난중일기 (war diary, in classical Chinese)
- Joseon wangjo sillok 조선왕조실록, Seonjo reign