Yi Sun-sin was a Korean naval commander during the late 16th century, known for his leadership in the Imjin War against Japan. He is celebrated for his innovative tactics and the development of the turtle ship, an armored warship that played a crucial role in naval battles. Despite facing overwhelming odds, Yi Sun-sin achieved several significant victories, including the famous Battle of Myeongnyang. His strategic brilliance and unwavering dedication to his country have made him a national hero in South Korea, and his legacy continues to inspire military leaders and historians today.