Battle of Dadaejin

The Battle of Dadaejin, along with the Siege of Busan, was one of the first battles of the Japanese invasions of Korea (1592–1598). The Battle of Busan and the Battle of Dadaejin occurred almost simultaneously. Dadaejin is also transliterated as "Tadaejin".

The Battle of Dadaejin
The Japanese quickly landed at the harbor and advanced upon the fortress. The battle pitted the Korean commander Yun Heung-sin (Hangul: 윤흥신 Hanja :尹興信) against Konishi Yukinaga, the first commander of the first division of the Japanese army. Yun's brother Yun Heung-je (Hangul: 윤흥제 Hanja :尹興梯) was also at the battle. The Korean commander quickly led his troops onto the walls for a defense, while Konishi landed in the harbor and charged, using the same tactic as So Yoshitoshi of draining the moat under cover of arquebuse fire. The arquebuses caught the Korean garrison at Dadaejin off guard. Similar to Busan, the Korean soldiers were terrified at the arquebuses and were incapable of effectively countering them.

The Koreans were unable to prevent the Japanese from draining the moat and thus having direct access to the defensive walls. The Japanese used siege towers, ladders, and the cover of arquebus-fire to scale the defense against barrages of arrows and rocks launched by the Koreans.

Yun waited for the first line of defense to be breached, feigned retreat, and mounted a massive counter-attack and caught the Japanese by surprise. After fierce mêlée, the main walls were breached and the city was taken. Like Busan, Dadaejin was looted, pillaged, and burned, with most of its civilian population massacred.

Conclusion
Konishi secured Dadaejin for reinforcements' landings. He immediately regrouped his army and marched towards Seoul, the Japanese army's main objective. Konishi and So Yoshitoshi, the attacker at Busan, met little resistance on their advancement (see Battle of Chungju and Battle of Sangju). The failure to defend Choryang Pass, a strategic defensive post, forced the Koreans to retreat and the Japanese armies reached the outskirts of Seoul in less than a month.