Battle of Egami-Hachiin
Date: 10/20 of Keichō 5 (1600)
Location: Egami-Hachiin in the Mizuma District of Chikugo Province of northern Kyūshū
Outcome: After the Battle of Sekigahara, members of the victorious Eastern Army including the Nabeshima clan led a large contingent to attack the rival Tachibana clan who had supported the Western Army. A retainer of the Tachibana named Ono Shigeykui led a smaller army to intercept them at Egami-Hachiin. After violent clashes, a surprise attack launched by a detached unit under Tachibana Nariie caused the Nabeshima forces to flee in disarray.
Lord: Tachibana Muneshige
Commanders: Ono Shigeyuki, Tachibana Munetsugu, Andō Norihisa, Ishimatsu Masayuki
Forces: 3,000 (2,000 under another theory)
Losses: Unknown total but including Andō Norihisa and Ishimatsu Masayuki from the vanguard
The Battle of Egami-Hachiin occurred on 10/20 of Keichō 5 (1600) in the aftermath of the pivotal Battle of Sekigahara in which the Eastern Army defeated the Western Army in the preceding month. In this battle, vanguard units of the Nabeshima army violently clashed with the Tachibana army led by a retainer named Ono Shigeyuki at Egami-Hachiin in the Mizuma District of Chikugo Province.
After the Battle of Sekigahara broke-out in 1600, Ono Shigeyuki, a retainer of the Tachibana clan, advocated for participation in the Western Army led by Ishida Mitsunari and attacked Kyōgoku Takatsugu (aligned with the Eastern Army) at Ōtsu Castle in the Shiga District of Ōmi Province in an event known as the Siege of Ōtsu Castle. In the wake of the defeat of the Western Army at Sekigahara, Nabeshima Naoshige, Katō Kiyomasa, and Kuroda Yoshitaka (Josui) proceeded to attack Yanagawa. On 10/14, the Nabeshima army totaling between 10,000 and 32,000 soldiers (depending upon the historical reference) split into two divisions and marched to Saga. In a bid to intercept them, Tachibana forces deployed in the direction of Hachiin. Tachibana Muneshige (a daimyō and the head of the clan) remained in his castle to show obedience to Tokugawa Ieyasu of the victorious Eastern Army, while Ono Shigeyuki (his chief retainer) deployed as the commander-in-chief of approximately 3,000 soldiers out of a total contingent of 13,000 forces. Based on another theory, 2,000 soldiers deployed while Shigeyuki commanded a battalion of 1,000 mounted soldiers). On 10/16, the Nabeshima army traversed the Chikugo River and toppled Kaizu Castle which was aligned with the Tachibana. On the morning of 10/19, a vanguard battalion of 3,000 troops encountered a surprise attack by a unit of 200 infantry soldiers and lost over twenty men but attacked Jōjima Castle. On 10/20, vanguard soldiers from the Nabeshima violently clashed with 3,000 to 5,000 soldiers from the Tachibana army led by Shigeyuki in this battle.
Owing to a miscommunication of military orders given by Matsukuma Kogen, a yoriki, or security official, of Shigeyuki, Andō Norihisa (Gorōemon) and Ishimatsu Masayuki (Yasubei) from the vanguard of the Tachibana forces broke the military rules and individually commenced hostilities, successively charging the Nabeshima encampment, while Tachibana Munetsugu (an adopted son of Tachibana Tsuguharu) of the third vanguard battalion penetrated deeply into the Nabeshima forces and fought valiantly. Nabeshima Shigetada, the head of the Nabashima vanguard forces, retreated to the main base of the Nabeshima at Gotanda. The Nabeshima forces, however, acted upon their initial strategy to surround and annihilate the enemy forces. Meanwhile, beginning with the death in battle of Tachibana Munetsugu after he did a solo charge into the enemy formation, Andō Norihisa and Ishimatsu Masayuki faced immediate counterattacks. Reinforcements from the second division led by Tachibana Shigezane (a member of the Fujikta-Totsugi clan, Totsugi Uemon-no-taifu), Tachibana Chika (Shigezane’s seventeen-year-old second son known as Zenjirō) and Nitta Shigezane (Hira Uemon, Kamon-no-suke) bravely attacked from the flank, but this was suppressed and they were killed in action.
In the rear guard, Yajima Shigenari (Jinbei) and Senju Yoshiun (security staff for Tsukushi Hirokado) vacillated and did not engage in the fighting so Andō Yukisada from the umamawari, or cavalry, and a young warrior named Totoki Korehisa (Shingorō, sixteen years old), in addition to Andō Norihisa and Ishimatsu Masayuki from the vanguard units, all died in battle. Ono Shigeyuki, as commander-in-chief, stiffly protected the bridge in front of the main encampment, whereupon he was surrounded by Nabeshima forces and fought valiantly, but after a counterattack by the Nabeshima, only fourteen to fifteen of his soldiers fighting alongside him remained. Shigeyuki himself incurred wounds after being struck by arquebus fire as well as arrows, but just before perishing, he safely retreated after Tachibana Nariie (who had been observing the naval forces of Kuroda Josui in the direction of Mizuta) led a detached unit of 300 soldiers on a courageous surprise attack against the Nabeshima forces, causing them to scatter in disarray.