Admiral Yi Sun-sin The Greatest Naval Strategist, Imjin War - Art Of War Generals

Admiral Yi Sun-sin - Turtle Ship

Admiral Yi Sun-sin is known as one of the greatest naval commander in history. When it comes to the art of war, he is worthy to be mentioned.

Throughout his naval career, Admiral Yi fought in at least 23 recorded naval engagements, all against the Japanese during the Imjin War from 1582 to 1598 and he never lost.

In most of these battles, the Japanese naval outnumbered Admiral Yi's fleet.

He is also known for his innovative Turtle Ship and his most famous victory was the Battle of Myeongnyang, where he had only 13 warships against 333 Japanese ships made up of (133 warships, and at least 200 logistical support ships).

Let's discover Admiral Yi's bio and what made him undefeatable.

Admiral Yi Sun-sin was born on April 28, 1545 in Hanseong, Korea.

His family was part of the Korean Deoksu Yi clan. His grandfather Yi Baek-rok (이백록; 李百祿) retired from politics when neo-Confucian reformer Jo Gwang-jo was executed in the Third Literati Purge of 1519.

His grandfather then moved to a village near where Jo Gwang-jo was buried.

Yi Sun-sin's father Yi Jeong (이정, 李貞) was likewise fed up with politics and did not enter government service as expected, coming from a yangban.

Yangban is a social class referring to nobels which mainly of highly educated civil servants and military officers.

One of the most important events of his early life was when Yi met and became friends with Ryu Seong-ryong (류성룡; 柳成龍; 1542–1607), a prominent scholar who became a Chief State Councillor which was the highest government position and was in command of the military during the Japanese invasions of Korea (1592–1598).

Yi's Military Career

In 1576, Yi sat and passed the military examination (무과; 武科). He is said to have impressed the judges with his archery but failed to pass the test when he broke a leg during the cavalry exam.

He re-entered for the military exam and this time passed the examination,

His first post was to the Bukbyeong (the Northern Frontier Army) military district in Hamgyeong province. At that time he was the oldest junior officer at the age of thirty-two.

There, Yi was battling and defending the border settlements against the Jurchen army and quickly he became known for his strategic skills and leadership.

In 1583, he lured the Jurchen into battle, defeated the bandits, and captured their chief, Mu Pai Nai. Yi had led a string of successful campaigns against the Jurchen tribes.

However, his brilliance and accomplishments in a short time in his career made his superiors jealous, and they falsely accused him of desertion during one of the battles. The conspiracy was led by his superior General Yi Il (이일; 李鎰; 1538–1601), who would much later fail to repel the Japanese invasion at the Battle of Sangju.

This tendency to sabotage and frame professional adversaries was very common in the later years of the Joseon military and government. Yi was stripped of his rank, imprisoned, and tortured.

After his release, Yi was allowed to fight as a lower-ranking soldier. After a short period, however, he was appointed as the commander of a military training centre and was later transferred to a small county, to be its military magistrate.

In 1590, Yi's efforts in northern Korea were meritorious he got promoted a few times and eventually was assigned as Commander of the Jeolla Province Left Naval District.

During that time, the royal court was in a state of confusion over the possibility of a war with Japan, now unified under the rule of feudal lord Toyotomi Hideyoshi,

And the unstable situation in Manchuria where a young and capable Jurchen chieftain named Nurhaci was gaining military strength.

Nurhaci's descendants would become masters of China as founders of the Qing Dynasty in a few decades time, after invading Korea in 1627 and 1637.

Yi assumed his new post at Yeosu on the 13th day of the 2nd lunar month of 1591 (March 13, 1591). From there, he was able to undertake a buildup of the regional navy, which was later used to confront the Japanese invasion force. He subsequently began to strengthen the province's navy with a series of reforms, including the construction of the legendary turtle ship.

The turtle ship

The turtle ship was one of Admiral Yi's secret art of war weapons.

Yi's greatest innovation was resurrecting and improving the turtle ship which was an experimental warship almost two centuries earlier.

With his creative mind and the support of his subordinates, Yi was able to devise the geobukseon or Turtle Ship.

The turtle ship is armoured and was a variant of the panokseon, the Korean cannon-armed warship.

The first turtle ship was launched on March 1592, just as the Japanese invasion of Korea began.

It was designed by Admiral Yi and held by around ten cannons on each side of the ship, with two cannons each at the prow (the front of the ship) and one at the stern (the rear of the ship).

The turtle ship was 28 meters long, 9 meters wide and with a height of 6 meters.

The ship's figurehead was in the shape of a dragon. The figurehead 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. The turtle ship's roof spikes prevented boarders from jumping down onto the roof without risking being injured.

There were two masts that held two large sails. The turtle ship was also steered and powered by twenty oars, each of which were pulled by two men during fair conditions and five in foul seas or combat.

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.

Turtle ship was the most famous part of Admiral Yi's naval fleet; however, he never deployed more than five in any one battle. The Joseon navy used cannons and fire arrows as its primary offensive naval weapon.

The Koreans have developed high-quality gunpowder technology and superior long-range canons.

The Japanese naval on the other hand rely on the arquebus which is a long gun and hand-to-hand combat.

The arquebus firing range was lethal up to 500 meters.

The Japanese implement the ship-boarding strategy, where they board the enemy's ship and engage in a sword fight.

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 are mostly used to spearhead attacks. They were designed to be used in narrow areas and around islands rather than the open sea.

Japanese invasion of Korea (1592 - 1598)

After the success of the unification in Japan, the Japanese warlord, Toyotomi Hideyoshi was still yearning for some accomplishment to solidify his legacy,.

He adopted his former boss, Oda Nobunaga's dream of a Japanese conquest of China and launched the conquest of the Ming dynasty through Korea.

Hideyoshi had been communicating with the Koreans since 1587 requesting a secure passage into China. As an ally of Ming China, the Joseon government of the time at first refused talks entirely, and in April and July 1591 also refused demands that Japanese troops be allowed to march through Korea.

The government of Joseon was concerned that allowing Japanese troops to march through Korea (Joseon) would mean that masses of Ming Chinese troops would battle Hideyoshi's troops on Korean soil before they could reach China, putting Korean security at risk.

In August 1591, Hideyoshi ordered preparations for an invasion of Korea to begin.

In 1592, Toyotomi Hideyoshi gave the order to invade Korea and use it as a forward base to conquer Ming China.

The Japanese forces saw overwhelming success on land, capturing both Hanseong, the capital of Korea, today called Seoul and Pyongyang, and completing the occupation of large portions of the Korean Peninsula in three months.

However, the Japanese were having a tough time sending their supplies to their ground forces to the north to fight China as the roads in Korea were not well developed.

The best alternative was to send their supplies by sea through the east of Korea. On that journey, the Japanese will have to pass Admiral Yi Sun-sin's naval warships.

Admiral Yi played a very crucial role in this war against the Japanese by blocking and restricting food, supplies and equipment being sent by sea.

Hideyoshi was fully aware of the need to control the seas during the invasion.

Having failed to hire two Portuguese galleons to help him, he increased the size of his own fleet to 1700 vessels, assuming that he could overwhelm the Joseon navy with numerical superiority.

There were many reasons why Admiral Yi was so successful against the Japanese fleets.

Why was Admiral Yi successful in his naval battles.

Admiral Yi, despite never having commanded a naval battle in his life, won the Battle of Okpo, the Battle of Sacheon, and several others in quick succession.

With the understanding of the principles of the art of war and his string of victories made the Japanese generals suddenly wary of the threat at sea.

He was very well aware of the intention of the Japanese to use Korea as a passage to conquer the Ming of China.

Most of the latest news he would have gotten was from his childhood friend Ryu Seong-ryong who was the Chief State Councillor which was the position of a Prime Minister of the time.

like what Sun Tzu would do, Admiral Yi hurriedly prepares his navy for the possibility of a war.

To creater a powerful defence system...

He checked the status of his soldiers, resources like granaries, and supplies, and replaced them where it was necessary. At the same time to strengthen his naval power, Yi resurrected and built the turtle ship, which was a considerable factor in his victories.

So he designed the turtle ship to fight the war based on the understanding of how the Japanese naval fought.

Yi had a great deal of knowledge of the southern Korean coast and he planned his battles using the sea current, tides and narrow straits to his advantage.

He also has a very strong reconnaissance. He has many informers who supply him with crucial information on the terrain, and the movement and location of the enemy.

In any warfare, using the right equipment is important. 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 which had 4 cannons. Japanese ship-mounted cannons were inferior to the Koreans in both range and power.

While 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.

Admiral Yi is aware of the strength of the Japanese naval and their style of fighting.

Admiral Yi's leadership 

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 fulfil 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.

Four campaigns of 1592

First Campaign (Battle of Okpo 1592)

The Japanese invasion of Korea began with the arrival of 400 transports bearing 18,700 men under the command of Konishi Yukinaga on 23 May 1592 for the Seige of Busanjin.

Over the next several weeks, the Japanese fleet ferried Toyotomi Hideyoshi's invasion force of 158,000 men to the Busan area, and the Japanese armies had advanced rapidly northward, and had seized the Korean capital of Hanseong by 16 Jun 1592.

As the Japanese now prepared to advance further north, logistics became an issue, and Japanese transports began exploring further up the west coast of the Korean peninsula as it was not practical to carry large amounts of supplies overland given the rough terrain and poor state of the roads.

At the time of the invasion, the Korean naval forces were split into regional commands.

Upon hearing the news of the fall of Busan to the Japanese, Gyeongsang Left Navy Commander Bak Hong ordered his weapons and stores destroyed and sank his fleet of 100 warships without giving a battle.

Likewise, after the fall of Dongnae, the Gyeongsang Right Navy Commander Wo Gyun panicked and attempted to abandon his ships to Hasando when he mistook a bunch of fishing ships for the Japanese fleet.

He later proceeded to destroy his weapons and stores and to scuttle his fleet. He was dissuaded from deserting his command by his subordinates, by which time he had only four vessels remaining.

Won Gyun called on Admiral Yi Sun-sin for assistance; however, as the commander of the Cholla Left Navy, he was not allowed to leave his region without permission from his superiors.

At the same time, Admiral Yi had several good reasons to delay.

He needed to acquire charts of the rocky coastal waters of Gyeongsang Province for his fleet to navigate safely, and he was also uncertain of the discipline of the men under his command and was forced to execute deserters to set an example, including on 12 June 1592, the day Hanseong fell to the Japanese.

Admiral Yi Sun-sin had hoped to combine his forces with that of Cholla Right Navy Commander Yi Eok-gi; however, when orders came from the capital, he was ordered to combine with the now non-existent forces of Wong Gyun instead.

With Wong Gyun's remaining four vessels, Admiral Yi Sun-sin had 39 warships under his command (24 large panokseon, 15 smaller hyeupson) and 46 smaller open boats.

When Admiral Yi Sun-sin and Won Gyun arrived near Geojedo on 16 June, a scouting vessel alerted them to the presence of Japanese ships anchored at the port of Okpo.

Admiral Yi Sun-sin's fleet approached Okpo on 17 June. Yi's flagship was in the centre of a line with the other heavy warships in the centre and light vessels to the left and right, and Won Gyun lingering at the rear of the formation.

When they entered the harbour they found more than 50 Japanese transport ships, mostly unmanned, and the crews looting in the village.

This angered Admiral Yi and he immediately attacked. Due to smoke around Okpo, the Japanese did not notice the arrival of the Korean fleet until it was upon them.

The Japanese panicked and quickly boarded their ships in an attempt to escape, but found they were surrounded and hemmed into the port.

After encircling the Japanese, the Koreans then commenced firing with their cannons. Under orders from Todo Takatora, the Japanese tried to fight back with their firearms but the arquebus while effective on land, did little damage to the thick wooden hulls of the Korean warships.

Admiral Yi Sun-sin proceeded to bombard the trapped Japanese transports with his cannon and fire arrows until the Japanese threw their weapons and armour overboard, abandoned the ship, and jumped into the water. In total, 26 Japanese transports were destroyed during the bombardment.

Yi Sun-sin resisted the impulse to land his men and to pursue the surviving Japanese on the island, as the risk was great and such an action would leave his fleet undermanned and vulnerable.

When a group of Admiral Sun-sin's men seized a Japanese ship, Won Gyun's ships fired on them, mistaking them for enemies.

After the battle, Admiral Yi Sun-sin immediately received news of another five Japanese ships within their vicinity and gave chase.

The Japanese fled to Happo harbour and abandoned their ships, which Yi ordered to be burned.

Soon after sunrise on 17 June 1592, Yi Sun-sin received news of another 13 Japanese ships nearby and on setting sail, found the Japanese transports at Jeokjinpo.

They destroyed 11 out of 13 ships. The Koreans then took the treasures from the Japanese wrecks and sailed back to Yeosu.

Admiral Yi Sun-sin arrived back at Yeosu on 18 June, from which he wrote a long report to the court.

Later, at the Battle of Sacheon, he first used his "secret weapon", the turtle ships, and defeated the Japanese again.

Second campaign (Battle of Sacheon)

Yi Sun-sin received news from Won Gyun that the Japanese had occupied Sacheon and the surrounding area.

Fearing that they were planning an attack on Yeosu, Admiral Yi Sun-sin set sail with 26 warships on July 8, 1592. He met up with Won Gyun at Noryang and ordered him to gather all the warships after the battle and then approached Sacheon.

Admiral Yi surveyed the surrounding area. A large cliff overlooked the city and Japanese soldiers were everywhere in the city.

Twelve very large Japanese warships were anchored in the harbour, along with numerous other smaller ships.

Admiral Yi knew that he could not attack the Japanese in a spearhead assault because he knew that the Japanese could direct arquebus fire down on the Koreans from the top of the cliffs.

Admiral Yi wanted to fight the Japanese in the open sea where there was more room to maneuver. Hoping to draw the Japanese into open waters, he turned his battleships around and withdrew.

Apparently, the Japanese commander had been observing the Korean movements and quickly ordered his captains to take a portion of the fleet anchored at Sacheon and attack the Koreans when he saw them withdraw. Taking the bait, the Japanese pursued the Koreans to the open sea.

The 1st deployment of the Turtle ships

The Battle of Sacheon was the first battle during which Admiral Yi deployed the turtle ship. By the time the Koreans and the Japanese were out on the open sea, it was nearly dark.

Admiral Yi had the turtle ship and his other vessels turn around quickly and unleash a hail of cannonballs and fire arrows. This had an immediate effect on the enemy warships, and the Japanese ships started taking heavy damage.

The fierce and sudden Korean attack shocked the Japanese.

But unlike the Battle of Okpo, the Japanese were ready and their soldiers fought bravely and returned fire with their arquebuses promptly.

However, the Japanese did not have a chance to board the Korean ships because of concentrated Korean cannon fire.

Also, the turtle ship was impossible to board in any way due to iron spikes on its roof. Then, the Japanese began to panic when the turtle ship smashed into Japanese lines, firing in every direction.

It was in the heat of the battle Admiral Yi was shot by a Japanese arquebusier. The Korean captains were shocked. However, the bullet only punctured the skin of his left arm leaving Admiral Yi with a very minor injury.

In a couple of hours, all the Japanese warship was destroyed.

Only a few small Japanese ships managed to flee and a few survivors struggled ashore.

The Battle of Sacheon sent shocking news to the Japanese command at the occupied Busan.

Third campaign (Battle of Hansan 1592)

In response to the Korean navy's success, Toyotomi Hideyoshi gave orders to the three admirals: Wakizaka Yasuharu, Kato Yoshiyaki and Kuki Yoshitaka to stop all ground operations for the time being and focus on naval operations.

Hideyoshi understood that if the Koreans won command of the sea, this would be the end of the invasion of Korea, and ordered the destruction of the Korean fleet, with Yi Sun Sin's head to be brought to him.

However, the three Japanese admirals arrived in Busan nine days before Hideyoshi's order was actually issued, and assembled a squadron to counter the Korean navy.

Eventually, Admiral Wakizaka completed his preparations, and his eagerness to win military honour pushed him to launch an attack against the Koreans without waiting for the other admirals to finish.

While the Japanese were preparing, the combined Korean navy of 70 ships under the commands of Admirals Yi Sun-sin and Yi Eok-Ki was carrying out a search-and-destroy operation.

On August 13, 1592, the Korean fleet sailing from the Miruk Island at Dangpo received local intelligence that a large Japanese fleet was nearby.

The following morning, the Korean fleet spotted the Japanese fleet of 82 vessels anchored in the straits of Gyeonnaeryang.

Because of the narrowness of the straits and the hazard posed by the underwater rocks, Admiral Yi sent six ships to lure out 63 Japanese vessels into the wider sea, and the Japanese fleet followed.

There the Japanese fleet was surrounded by the Korean fleet in a semicircular formation called "crane wing" by Admiral Yi. With at least three turtle ships (two of which were newly completed) spearheading the clash against the Japanese fleet.

The Korean vessels at the beginning continuously fired cannonballs into the Japanese formation.

Then the Korean ships penetrated the Japanese warship formation while maintaining enough distance to prevent the Japanese from boarding; Admiral Yi permitted hand-to-hand combats only against severely damaged Japanese ships.

The battle ended in a Korean victory, with Japanese losses of 59 ships – 47 destroyed and 12 captured in the Battle of Hansan Island.

Several Korean prisoners of war were rescued by the Korean soldiers throughout the fight.

Admiral Wakisaka managed to escape with the speed of his flagship. When the news of the defeat at the Battle of Hansando reached Toyotomi Hideyoshi, he ordered that the Japanese invasion forces cease all naval operations.

On August 16, 1592, Admiral Yi Sun-sin led their fleet to the harbour of Angolpo where 42 Japanese vessels were docked.

Admiral Yi tried to lure the Japanese warships out to the open sea to fight but the Japanese refused to fall for the bait.

Admiral Yi then moved into Angolpo fired canons and shot arrows with fire and destroyed all the 42 anchored Japanese warships.

4th Campaign (Battle of Busan 1592)

The Japanese navy retreated to Busan and focused on protecting and rebuilding their positions.

Commander Yi sent spy ships to Busan port and found out there were about 470 warships there.

Commander Yi believed that the Japanese were retreating to their country, So Gyeongsang Province Governor (慶尙右水營) Kim Soo requested that Commander Yi block their sea route.

Therefore, Commander Yi with Won Gyun and Yi Eok-ki, they have a total of 166 vessels.

Off the coast of Busan, the united Joseon fleet realized that the Japanese navy had readied their ships for battle, and the Japanese army had stationed themselves around the shoreline.

The united Joseon fleet assembled in the "Long Snake" formation, with many ships advancing in a line, and attacked straight into the Japanese fleet.

Overpowered by the Joseon fleet, the Japanese navy abandoned their ships and fled to the coast where their army was stationed.

The Japanese army and navy joined their forces and attacked the Joseon fleet from the nearby hills in desperation.

The Joseon fleet shot arrows from their ships to defend and restrict their attacks and, in the meantime, concentrated on their cannon fire to destroy Japanese vessels.

The Korean ships fired on the Japanese fleet and burned them using fire arrows while the Japanese fired using canons and arquebus on them from above in their forts.

Even with cannons captured at Busan, the Japanese did little damage to the Korean warships. By the time the day had ended, 128 Japanese ships had been destroyed. Yi Sun-sin gave orders to withdraw, ending the battle.

Aftermath of four campaigns of 1592

Yi was victorious in every single operation (at least 15 battles) of the four campaigns of 1592. His campaigns resulted in hundreds of sunken Japanese warships, transports, supply ships and thousands of Japanese naval casualties.

In 1593, Admiral Yi was appointed to command the combined navies of the three southern provinces with the title Naval Commander of the Three Provinces (삼도수군통제사; 三道水軍統制使) which gave him command over the Right and Left Navies of Jeolla province, the Right and Left Navies of Gyeongsang province, and the Navy of Chungcheong province.

Japanese Double Agent Plot (Spy)

In this plot, spies are used as part of the art of war as part Sun Tzu art of war tactics. This time the Japanese uses this tactics to eliminate their enemies.

Admiral Yi caused a lot of disruption for the Japanese ships carrying food, weapons, and reinforcements to their army. His warships attacked and delayed the Japanese ships to the point that

As Admiral Yi won battle after battle, Hideyoshi and his commanders became anxious as they neared Busan.

Yi constantly attacked and delayed supply ships bringing food, to one point, the entire invasion was halted just before attacking Pyongyang when supplies and troops failed to reach the First and Second Divisions.

The only solution is to eliminate Admiral Yi.

Taking advantage of the many internal court rivalries of the Joseon Dynasty, the Japanese came up with a plan.

A Japanese double agent named Yoshira (要時羅) was sent to the Joseon general Kim Gyeong-seo (김경서; 金景瑞; 1564–1624) and convinced the general that he would spy on the Japanese.

Yoshira played this role so well that Kim began believing anything he would say.

One day, he told General Kim Gyeong-seo that the Japanese general Katō Kiyomasa would be coming on a certain date with a great fleet for another attack on the south shores and insisted that Admiral Yi be sent to lay an ambush.

General Kim agreed and sent the message to Field Marshal Gwon Yul, Commander-in-Chief of the Joseon military, who, in turn, sent the message to King Seonjo.

King Seonjo, who was desperate for victories to loosen the Japanese grip on his kingdom, gave permission for the attack.

When General Kim gave Admiral Yi his orders, the admiral refused to carry them out, for he knew that the location given by the spy was studded with sunken rocks and was thus extremely dangerous.

Admiral Yi also refused because he did not trust the words of spies.

When General Kim informed the king of Admiral Yi's refusal, the admiral's enemies at court quickly insisted on his replacement by General Won Gyun, former commander of the Gyeongsang Province Western Fleet and commander of the Jeolla Province Ground Forces.

They advised that Admiral Yi be arrested.

As a result, in 1597, Yi was relieved of command, placed under arrest, and taken to Seoul in chains to be imprisoned and tortured.

Yi was tortured almost to the point of death by using simple torture tactics such as whipping, flogging, burning, the cudgel, or even the classic technique of leg-breaking torture.

King Seonjo wanted to have Yi killed, but the admiral's supporters at court, chiefly the minister Jeong Tak, convinced the king to spare him due to his past service record. The prime minister, Yu Seong-ryong, who was Yi's childhood friend and his main supporter, remained silent during this deadly hour. Spared the death penalty, Admiral Yi was again demoted to the rank of a common infantry soldier under General Gwon Yul.

Despite his low rank, many officers treated him with respect, since they knew that the admiral did nothing wrong. Yi would stay under General Gwon Yul's command for a short while until Won Gyun's death at the Battle of Chilchonryang, which would lead to his reinstatement.

Joseon's defeat at Chilchonryang and the reinstatement of Admiral Yi

With Yi stripped from his ranks, in 1596, Hideyoshi again ordered an attack on Joseon.

The second Japanese invasion landed in the first month of 1597 with a force of 140,000 men transported on 1000 ships.

In response, the Ming Dynasty of China sent thousands of reinforcements to aid Joseon.

With the help of the Ming, the Joseon army was able to halt the Japanese offensive and push it back during the winter of 1597, before the Japanese were able to reach the Joseon capital of Hanseong.

On the high seas, Yi's successor Won Gyun failed to act on the reports from his scouts and allowed the Japanese to land critical reinforcements at Sosang Harbor for their land offensive unopposed.

Without adequate reconnaissance or planning, Won Gyun decided to attack with the entire naval force of Joseon at his disposal; a fleet consisting of 150 warships operated by 30,000 men that had been carefully assembled and trained by Admiral Yi.

Won Gyun left Yeosu with the fleet and sailed into waters full of treacherous rocks where the Japanese ambushed the Joseon fleet in the Battle of Chilchonryang on August 28, 1597.

Ignorant of the strength and disposition of the enemy, Won was cornered by a Japanese fleet of 500 to 1000 ships which immediately closed for melee combat, denying the Joseon ships the advantages of superior seamanship and cannon fire.

The exhausted Joseon sailors were reduced to fighting boarding actions while heavily outnumbered and were totally slaughtered.

The Joseon fleet was decimated with only 13 warships surviving under Admiral Bae Seol, who fled before battle was fully engaged to save the warships under his command.

After the destruction of the Joseon fleet, Won Gyun fled to an island with a band of survivors but was killed by waiting Japanese soldiers from the nearby fort.

The other commander, Yi Eok-gi fought to the end and drowned.

The Battle of Chilchonryang was the only naval victory for the Japanese during the war against Joseon. When King Seonjo and the royal court learned of the catastrophic defeat, they hurriedly pardoned and reinstated Admiral Yi as commander of the greatly reduced Joseon fleet.

Battle of Myeongnyang

Admiral Yi managed to locate the 13 warships and reunite the 200 surviving sailors, and together with his flagship, Admiral Yi was ready for battle.

In the belief that the Joseon fleet would never be recoverable, King Seonjo sent an edict to Admiral Yi to abandon the warships and take his men to join the ground forces under General Gwon Yul.

Admiral Yi responded with a letter written "...your servant still doth have twelve warships under his command and he is still alive, that the enemy shall never be safe in the West Sea."

Inspirited by their victory at Chilchonryang, the four Japanese admirals, Kurushima Michifusa, Todo Takatora, Kato Yoshiaki, and Wakisaka Yasuharu sailed out of Busan Harbor with a fleet of over 300 ships, confident in being able to defeat Admiral Yi.

Getting rid of the Joseon naval fleet once and for all would mean unrestricted movement of supplies and reinforcements from Japan for the offensive drive on land towards Hanseong and beyond.

With only 13 warships Admiral Yi carefully planned and studied for potential battlefields.

In October 1597, Admiral Yi lured the Japanese fleet into the Myeongnyang Strait, by sending a fast warship near the Japanese naval base and luring the Japanese fleet out of anchorage.

The overconfident Japanese naval assumed that this was a Joseon scouting ship and that pursuing it.

They believe it would lead to the location of Admiral Yi, allowing them to destroy the remnants of the Joseon fleet.

What they did not know was that they were being lured into a trap. Admiral Yi decided on this location for battle for several reasons.

Myeongnyang Strait had currents, eddies, and whirlpools so powerful that ships could only enter safely a few at a time. The north–south tidal flow reversed every three hours, limiting the time that the Japanese could mount an offensive. The strait was sufficiently narrow that it would prove impossible for the Japanese to flank or envelop the numerically inferior Joseon fleet.

The deep shadows of the surrounding hillsides provided the Joseon ships with concealment. On that particular day, there was also a heavy mist, dramatically reducing visibility in favour of the Joseon fleet. Therefore, despite being vastly outnumbered, Admiral Yi used the terrain restrictions to neutralize the Japanese navy's staggering numerical advantage.

The Japanese fleet of approximately 333 ships (133 warships, at least 200 logistical support ships) entered Myeongnyang Strait in groups. The Japanese ships that made it through were met by 13 Joseon warships obscured by the shadows of the surrounding hills, ready with archers and cannons, and the melee-based Japanese found themselves unable to fight effectively and break through the superior Joseon ranged fire.

The unpredictable current eventually wreaked havoc on the Japanese; their ships found themselves unable to manoeuvre and collided with each other when the tide reversed, while also presenting a perfect target for the Joseon naval artillery.

Admiral Yi was astonishingly able to rout a force that outnumbered him more than 25 to 1 in ships alone. About 31 of the 333 Japanese ships that entered the Myeongnyang Strait were destroyed or damaged.

Joseon losses on the other hand were around ten casualties and no ships lost.

Kurushima Michifusa was killed on his flagship by Joseon naval archers; his body was fished out of the water, and his severed head was put on display to further demoralize the Japanese fleet.

Admiral Yi's incredible victory at the Battle of Myeongnyang was a big blow to the Japanese.

Their ground forces were on the verge of invading Hanseong were cut off from a steady flow of supplies and reinforcements, and forced to pull back.

Today, the battle is celebrated in Korea as one of Admiral Yi's greatest victories. No other engagement involving such an outnumbered fleet has resulted in such a disproportionate victory, making it one of the greatest achievements in naval warfare.

The battle of Noryang and the death of Admiral Yi

September 18th, 1598, Feudal lord Toyotomi Hideyoshi passed away. The new Japanese governing council then ordered the Japanese army to return to Japan.

During that time, Admiral Yi and Chen from the Ming dynasty put a blockade on Konishi Yukinaga and prevented them from retreating to Japan.

On December 15, 1598, the Japanese fleet under the command of Shimazu Yoshihiro gathered at Sachon Bay, on the east end of Noryang Strait.

Shimazu's mission was to help Konishi Yukinaga to lift the blockade and return to Japan.

Admiral Yi, meanwhile, knew exactly where Shimazu was, after receiving reports from scouts and local fishermen.

At this time, the Joseon naval fleet consisted of 82 panokseon and three turtle ships, with 8,000 soldiers under Admiral Yi.

The Ming fleet consisted of six large war junks, 57 lighter war galleys and two panokseon given to Chen Lin by Admiral Yi, with 5,000 Ming soldiers of the Guangdong squadron and 2,600 Ming marines who fought aboard Joseon ships.

Which was a total of 148 ships. The Japanese had around 500 ships.

The battle began at two o'clock in the early morning of December 16, 1598. Like Admiral Yi's previous battles, the Japanese were unable to respond effectively to the Korean's tactics.

The tightness of Noryang Strait hindered lateral movement, and Admiral Yi's manoeuvres prevented the Japanese fleet from boarding their enemies' vessels, their primary naval tactic.

As the Japanese retreated, Admiral Yi ordered a vigorous pursuit. During this time, a stray arquebus bullet from an enemy ship struck Admiral Yi, near his left armpit.

Knowing that the wound was most likely fatal, and fearing a repeat of the Battle of Chilchonryang, the admiral uttered, "The war is at its height – wear my armour and beat my war drums. Do not announce my death." He died moments later.

Only two people witnessed his death: Yi Hoe, Yi's eldest son, and Yi Wan, his nephew.

Admiral Yi's son and nephew struggled to regain their composure and carried the admiral's body into his cabin before others could notice. For the remainder of the battle, Yi Wan wore his uncle's armour and continued to beat the war drum to encourage the pursuit.

Most of the Japanese warships were destroyed.

It was said that only 50 Japanese ships escaped and returned to Japan.

Konishi Yukinaga and his warships did not make any effort to assist Shimazu Yoshihiro in the battle but instead, they took another route to retreat to Japan.

Konishi Yukinaga left his fortress on 16 December 1598 and his men were able to retreat by sailing through the southern end of Namhae Island, bypassing both the Noryang Strait and the battle.

By the 21st of December, all the Japanese Generals returned to Japan and the last ship that sailed to Japan was on 24th December 1598.

This brings an end to seven years of war.

Admiral Sun-sin's body was brought back to his home town in Asan to be buried next to his father, Yi Chong (by Korean tradition).

The court gave him the posthumous rank of minister. Shrines, both official and unofficial, were constructed in his honour. In 1643, Yi was given the title of Chungmugong, "duke or lord of loyal valour".