Yi Sun-sin (April 28, 1545 – December 16, 1598, ) was a Korean naval commander, famed for his victories against the Japanese navy during the Imjin war in the Joseon Dynasty. One of the most revered figures in Korean history, Yi is well-respected for his exemplary conduct on and off the battlefield not only by Koreans, but by Japanese Admirals as well.[1] Military historians have compared his naval genius to that of Admiral Horatio Nelson.[2] His title of Samdo Sugun Tongjesa ,literally meaning "Naval Commander of the Three Provinces," was the title for the commander of the Korean navy until 1896.

Perhaps his most remarkable military achievement occurred at the Battle of Myeongnyang. Outnumbered 333 ships to 13, and forced into a last stand with only his minimal fleet standing between the Japanese Army and Seoul, Yi delivered one of the most astonishing defeats in military history.

Despite never having received formal naval training or participating in naval combat prior to the war, and constantly being outnumbered and outsupplied, he went to his grave as one of few admirals in world history who remained undefeated after commanding as many naval battles as he did (at least 23).[3][4]

Yi died at the Battle of Noryang on December 16, 1598. With the Japanese army on the verge of being completely expelled from the Korean Peninsula, he was mortally wounded by a single bullet. His famous dying words were, "The battle is at its height...beat my war drums...do not announce my death."

The royal court eventually bestowed various honors upon him, including a posthumous title of Chungmugong ( Duke of Loyalty and Warfare), an enrollment as a Seonmu Ildeung Gongsin (First-class military order of merit during the reign of Seonjo), and two posthumous offices, Yeonguijeong ( Prime Minister), and the Deokpung Buwongun ( The Prince of the Court from Deokpung). Yi remains a venerated hero among Koreans today. ---From Wikipedia: http://en.wikipedia.org/wiki/Yi_Sun-sin

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During ImJin War, there was a Korean admiral named Yi Soon Shin (YiSunSin in wikipedia) who won 23 out 23 sea battles against Japanese invaders. He's undefeated. Here is a brief naval battle table: http://yisunsin.prkorea.com/battles.htm [inactive]

If you look at the table, the major battles are
1) the battle of Myeongryang (13 Korean warships vs 300 Japanese warships, which is 1500 Korean soldiers vs 120,000 Japanese samurai)

2) the battle of Busanpo (74 Korean warships and 92 small vessels vs 470 Japanese warships) the result is only 6 Korean soldier dead and 130 Japanese warships destroyed)

Also,
"In 1592, After the Japanese invasion, Yi Sun-Shin achieved distinguished victories after defeating 359 Japanese battleships killing about 30,000 Japanese samurai in four wars within one year.
With his prominent strategies and tactics, he achieved the world best triumphs by sinking about 700 battleships and capturing 23 battleships during the entire period of war. During the Japanese invasion three great victories were, the Hansando, the Haneju, and the Jinju."

I found a very good site that shows an animation if you want to know how they won the battles. Here it is: http://www.gbs.go.kr/en/images/imjin/cyber.html [inactive]


------GeoBukSeon (The Turtle Ship)------
During the 7 year ImJin War against Japan, Admiral Yi Sun Shin invented GeoBukSeon ship with his officers and soldiers. It's basically a turtle looking ship with thorns on its back and cannons on both its sides. For more info:

http://yisunsin.prkorea.com/arsenal.htm [inactive]
http://www.e-sunshin.com/eng/ach/ach_02.htm [inactive]
http://www.gbsun.com/index_132.htm [inactive]

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the timeline of his history and the Imjin War: http://yisunsin.prkorea.com/timeline.htm [inactive]

During the war, he also wrote "The War Diary" which has records about the events. http://www.e-sunshin.com/eng/ach/ach_03.htm [inactive]

the most famous quotes by Admiral Yi = http://yisunsin.prkorea.com/quotes.htm [inactive]