The Battle of Sacheon was a siege and naval engagement fought in 1598 during the second campaign of the Japanese invasions of Korea (1592-1598), also known as the Imjin War. It took place around Sacheon, a coastal town in present-day South Korea.
The battle involved a combined Ming-Joseon force besieging a Japanese castle at Sacheon. Japanese General Shimazu Yoshihiro successfully defended the castle, inflicting significant casualties on the allied Ming-Joseon forces.
The siege proved difficult for the Ming-Joseon army due to the strong defensive fortifications erected by the Japanese and their ample supplies within the castle. The battle culminated in a major explosion, the cause of which is disputed. Korean sources claim it was due to a Korean soldier detonating explosives in the castle walls. Japanese sources attribute it to an accidental explosion of gunpowder stores. Regardless of the cause, the massive explosion devastated a large portion of the attacking force and led to the retreat of the Ming-Joseon army.
The Battle of Sacheon is considered a significant Japanese victory in the later stages of the Imjin War, showcasing the defensive capabilities of Japanese castles and their ability to withstand prolonged sieges. Despite the Ming-Joseon forces having superior numbers, the strategic placement and strong fortifications of the Japanese garrison, coupled with the catastrophic explosion, resulted in a costly defeat for the allies. The victory at Sacheon allowed the Japanese to maintain their presence on the Korean peninsula until Hideyoshi's death later that year ultimately led to their withdrawal.