born April 28, 1545, Seoul, Korea
died Dec. 16, 1598, off Noryang
Korean admiral and national hero.
He worked on developing the kŏbuksŏn ("turtle ship"), thought to be the first ironclad battleship. As a result of Yi's preparations, his forces, unlike most of the Korean military, were ready to fight when the Japanese under Toyotomi Hideyoshi invaded in 1592. His sea victories effectively cut off the Japanese troops in Korea from their supplies. In 1597 he was falsely accused of disloyalty and demoted to the rank of common soldier. When the Japanese launched a second invasion and largely destroyed the Korean navy, Yi was reinstated and soon restored Korea's control of the seas. He was killed by a stray bullet as he pursued the retreating Japanese.