Siege of Ulsan Castle: Kato Kiyomasa Holds Out against the Ming and Korean Army in the Keicho Campaign

From the 22nd day of the 12th month of Keicho 2 to the 4th day of the 1st month of Keicho 3 (old calendar; 29 January to 9 February 1598 in the Gregorian calendar), a Ming and Korean army besieged the Japanese castle then under construction at Ulsan in Korea, and Kato Kiyomasa and others held it. The result was a Japanese victory. The Ming and Korean forces withdrew toward Gyeongju, and the Japanese pursued them for about 30 ri.

The two sides and their strength

The Ming and Korean side was commanded by Yang Hao and Ma Gui of the Ming and Gwon Yul of Korea. Their combined strength is given as about 57,000, made up of 44,800 Ming and 12,500 Korean troops.

On the Japanese side the central figure in the defense was Kato Kiyomasa, and Asano Yukinaga and Ota Kazuyoshi were also inside the castle. Mori Hidemoto, Kikkawa Hiroie, Tachibana Muneshige, Kuroda Nagamasa, Hachisuka Iemasa and others went to its relief. The garrison is given as about 10,000 and the relief force as about 13,000, though sources dispute these figures.

The surprise attack and the fall of the outer works

The castle was not yet finished, and there were temporary Japanese huts outside it. Ming vanguard cavalry first struck these huts and burned them. Kiyomasa returned to the castle by boat from Seosaengpo and took command.

On the 23rd the outer works were broken, but the Japanese held in the inner citadel. Attacks from the 24th to the 29th were beaten off.

Shortage of food and water, and the call to surrender

As the siege went on, the castle ran extremely short of food and water. On the 29th the besiegers sent envoys urging surrender. Kiyomasa showed willingness to negotiate, including an exchange of prisoners, and so gained time.

Meanwhile the Japanese relief forces gathered at Seosaengpo from the 26th of the 12th month to the 2nd of the 1st month.

The final assault and the withdrawal

On the night of the 3rd of the 1st month Yang Hao and Ma Gui launched a last general assault, which failed. On the 4th the Ming and Korean forces began to withdraw toward Gyeongju, and the Japanese pursued for about 30 ri.

Result, losses and aftermath

Losses are given as about 2,000 for the Ming and 3,000 to 4,000 for the Koreans, though the figures disagree. The number of enemy dead counted by the Japanese after the battle is given as 10,386.

After the battle Yang Hao was dismissed. Toyotomi Hideyoshi, acting on the reports of his inspectors, punished Hachisuka Iemasa and others, but the punishment was revoked in Keicho 4 (1599), after Hideyoshi's death.

Not to be confused with the Second Siege of Ulsan Castle

From late in the 9th month to early in the 10th month of Keicho 3 a second siege of Ulsan took place at the same site. There too Kiyomasa held the castle, and he withdrew on the 18th of the 11th month, setting the castle on fire. This article deals with the first battle, fought at the end of Keicho 2 and the start of Keicho 3.