Joseon Mountain Fortress System

Timeline

1. 1592Southern and central Joseon · Korean PeninsulaAfter Japanese forces landed in April 1592, coastal strongholds like Busan and Dongnae quickly fell. Joseon shifted defensive focus to existing mountain fortresses and defensible walled towns, mobilizing laborers to raise walls, dig ditches, and stockpile grain and weapons. These positions in Gyeongsang, Jeolla, Gyeonggi, and elsewhere were a wartime strengthening of existing fortification traditions, not a newly planned single fortress network.
2. 1592–1593Jinju Fortress · Gyeongsang ProvinceFirst Battle of Jinju (Nov 8–13, 1592, Gregorian): Jinju magistrate Kim Simin led soldiers and civilians in holding the fortress; it did not fall, and Kim was killed by gunfire in the fighting. Battle of Heungseongsanseong, March 14, 1593 (Gregorian; lunar Feb 12): Gwon Yul with about 2,300 men held cliff-top wooden palisades, repelling the Japanese with bows, artillery, and hwachas. Jinju fell in the second Battle of Jinju in 1593, with Kim Cheon-ik and others dying for the state.
3. 1593–1598Pyongyang, Hanseong, and Gyeonggi mountain fortresses · Korean PeninsulaAfter Ming forces entered Korea in 1593, the Joseon–Ming allied armies organized counteroffensives centered on Pyongyang and Hanseong. Fortifications and mountain fortresses in Jeongsan, Cheongju, Hwanghae Province, and elsewhere continued supply and blocking roles, coordinating with campaigns of Ming generals Li Rusong and Ma Gui. Existing mountain fortresses were again used for defense during the second invasion (1597–1598), until the war ended in 1598.