조선왕조실록
A naval engagement took place on 1 September 1592 during the first phase of the Japanese invasions of Korea. It was a Korean surprise attack on the fleet of Toyotomi Hideyoshi stationed at Busan. Over the course of the battle, Japanese forces lost 100 ships while no Korean ships were lost. Officer Woon () and six Korean soldiers, as well as countless Japanese soldiers were killed. However, ultimately, the Korean fleet retreated, failing to take over Busan. In the Annals of the Joseon Dynasty (a Korean official history, written by a bureaucrat of the Korean government located in Hanyang District), it is recorded that the Korean navy failed to defeat the Japanese at Busan. However, in other primary historical sources, such as the official Joseon compendium (李忠武公全書) written by Joseon bureaucrats, and the War Diary of Yi Sun-sin and his military reports, it is recorded as a decisive Korean victory. Modern historians have also summarized the battle as a decisive Korean victory. Some Korean historians believe the War Diary of Yi Sun-sin more than Annals of the Joseon Dynasty when they study the Imjin war because he was the on-scene commander.