The Japanese invasion force departed from Tsushima Island under the command of Konishi Yukinaga and arrived at Busan harbor without resistance. Chong Pal, the garrison commander, happened to be hunting on Yeong Island off the harbor when he spotted the approaching fleet and rushed back to organize a defense. His urgency was not matched elsewhere in the chain of command. The Korean Joseon fleet of 150 ships sat idle at port while Gyeongsang Left Navy Commander Pak Hong reported the arrival to his counterpart Won Kyun, who speculated that the massive armada might simply be a very large trade mission. It was, perhaps, the most catastrophically optimistic assessment in Korean military history. Meanwhile, the Japanese commanders divided their force: So Yoshitoshi, the daimyo of Tsushima who had visited Korea on a diplomatic mission only three years earlier, led the main contingent against Busan while Konishi attacked the nearby fort of Dadaejin.

Early on May 24, So Yoshitoshi made one more attempt at negotiation. He called on Chong Pal to stand aside, promising safety for the garrison if they let the Japanese pass. Chong Pal's refusal was not defiant bluster but a statement of professional obligation: he was duty-bound to oppose the advance unless he received orders from Seoul to do otherwise. No such orders came, and the Japanese attacked. They tried the south gate of Busan Castle first but took heavy casualties and shifted to the north gate. Japanese soldiers seized the high ground on the mountain behind the castle and fired down into the compound with arquebuses -- firearms that outranged the Korean defenders' bows and spears. When the garrison ran out of arrows, the outcome was decided. Chong Pal was struck by a bullet and killed around nine in the morning. His death collapsed the remaining defenders' morale, and the castle fell.

What followed the castle's fall was not the orderly occupation of a conquered fortification. Japanese records document that 8,500 Koreans were killed at Busan and 200 taken prisoner. Contemporary accounts report that soldiers, civilians, and even animals were beheaded in the aftermath. The scale of the killing was intended to send a message to other Korean garrisons along the route to Seoul -- a message that the next fortress at Dongnae, ten kilometers to the northeast, would receive the following day. Pak Hong, the naval commander who had earlier dismissed the fleet as merchants, watched the fall of Busan from a distance. Rather than engage the Japanese at sea -- where his 100 ships, including more than 50 cannon-armed warships, might have made a difference -- he scuttled his entire fleet and destroyed his weapons and provisions to keep them from Japanese hands. Then he abandoned his men and fled to Hanseong, the capital.

With Busan secured, the port became the primary staging ground for every subsequent Japanese deployment during the invasions that lasted from 1592 to 1598. The armies of Kato Kiyomasa and Kuroda Nagamasa landed here, and Busan served as Japan's main supply base throughout the conflict. The city's significance as a military gateway between Japan and the Korean Peninsula would echo through centuries of subsequent history. Today, a statue of Chong Pal stands next to the Japanese Consulate in Busan -- a deliberate placement that keeps the memory of his refusal and his death in conversation with the ongoing relationship between the two countries. The nearby Chungnyeolsa Shrine honors the soldiers and civilians who died in the siege, their sacrifice measured not by victory but by the choice to resist when resistance was hopeless.