Battle of Myōzenji
Date: Seventh month of Eiroku 10 (1567)
Location: Near the village of Sawada in the Jōtō District of Bizen Province
Outcome: The Mimura clan, led by Mimura Motochika, lost Myōzenji Castle and was expelled from Bizen Province by the rival Ukita clan led by Ukita Naoie who deployed ingenious tactics to achieve victory in a series of dramatic clashes on behalf of his lord, the Uragami clan.
The Battle of Myōzenji occurred in the seventh month of Eiroku 10 (1567) near the village of Sawada in the Jōtō District of Bizen Province. After acquiring control of Bitchū Province, the Mimura clan aimed to expand their governance to Bizen. In this engagement, the Mimura were opposed by Ukita Naoie, who, at the time, served as a notable retainer of the Uragami clan. Owing to the collapse of the Mimura forces, this is also known as the Collapse at Myōzenji.
In 1559, Ukita Naoie, upon orders from his lord, Uragami Munekage, executed Nakayama Nobumasa, the lord of Kameyama Castle located on the plains of Bizen. Around this time, Mimura Iechika joined his ally, Mōri Motonari, in a conflict against the Amago clan. Together with the Mōri, the Mimura helped to weaken the Amago forces, leaving them with only Gassantoda Castle. Iechika then took leave from Motonari to attack Kanagawa in Bizen with the aim of gaining a foothold in the province.
With the consent of Motonari, Iechika proceeded with the invasion of Bizen, attacking Okayama and Funayama castles, compelling the surrender of Kanamitsu Munetaka and Susuki Buzen-no-kami, and garnering control of both castles. In 1565, the Mimura forces invaded Mimasaka Province and invaded Mitsuboshi Castle defended by Gōtō Katsumoto, the son-in-law of Naoie. Additional forces sent by Naoie protected the castle, causing the invading army to withdraw.
In the second month of 1566, once again, Iechika invaded Mimasaka but, upon orders from Naoie, Endō Matajirō and Endō Toshimichi assassinated Iechika with arquebuses. This forced the Mimura army to retreat to Bitchū Province. Following the demise of Iechika, Mimura Motochika succeeded his father as head of the Mimura clan.
In 1566, Naoie aimed to expand the territory under this control in Bizen, so he built a castle on Mount Myōzenji near the village of Sawada in the Jōtō District of Bizen, and stationed troops there.
In the seventh month of 1567, Mimura forces launched a nighttime attack against Myōzenji Castle. Having been caught off-guard, the Ukita suffered the loss of fifty to sixty soldiers and were forced to withdraw from the castle. Consequently, the Mimura took control of the castle, whereupon Motochika assigned 150 men under the command of Neya Yoshichirō and Yakushiji Yashichirō to defend the castle. Upon learning of the fall of Myōzenji Castle, Naoie launched a plot whereby he persuaded several lords who earlier surrendered to the Mimura to betray them, including Kanamitsu Munetaka of Okayama Castle, Nakashima Motoyuki of Nakashima Castle, and Susuki Buzen-no-kami of Funayama Castle. This resulted in the isolation of Myōzenji Castle within enemy territory.
Naoie sent a messenger to Myōzenji to demand surrender and propose that the occupants turn-over the castle without bloodletting, but Yoshichirō and Yashichirō did not believe that the other lords had betrayed them in favor of the Ukita, so they rejected the demand and sent their own messenger to their home province of Bitchū to request reinforcements. Having ascertained these actions by the defenders, Naoie promptly attacked Myōzenji and devised a plan to lure the main contingent of the Mimura army into his territory to annihilate them. First, he gave instructions to Kanamitsu Munetaka to solicit the Mimura army to serve as a rear guard. Munetaka adhered to these instructions by dispatching a messenger to Ishikawa Hisamoto in Myōzenji to propose that the Kanamitsu would coordinate with the defenders in the castle to launch a pincer attack against the Ukita army. Mimura Motochika received a similar message from Myōzenji so he decided to deploy forces.
The outbreak of hostilities
An army of over 10,000 men, comprised of the Mimura soldiers led by Motochika, together with forces commanded by Ishikawa Hisamoto, Ueki Hidenaga, and Shō Motosuke, assembled and then invaded Bizen Province. In response, Naoie departed from his home base at Kameyama Castle, positioned over 5,000 forces in five columns, and sent the vanguard unit to attack Myōzenji Castle. Commanders of the forces from Bizen held a war council at Karakawa-omote and decided for Shō Motosuke to lead a forward division of 7,000 men, and for Kanamitsu Munetaka to serve as the guide for troops to advance south, widely circumvent Okayama Castle, traverse the Asahi River, and proceed to Myōzenji Castle. Ishikawa Hisamoto would command the middle division of 5,000 men, advance to the village of Haraoshima, and assault the Ukita forces attacking Myōzenji from behind. As the supreme commander, Motochika would lead a contingent of 8,000 men guided by Nakashima Motoyuki, cross the Asahi River, and pass-through the village of Shinogoze to storm Kameyama Castle.
Upon learning of the plans of the Mimura forces, Naoie immediately gave the command for a major assault against Myōzenji which soon fell.
Defeat of the vanguard of the Mimura army
The Mimura forces had planned for a coordinated pincer attack with the soldiers based at Myōzenji, but, after the sudden attack by Naoie, that plan collapsed. Meanwhile, after the vanguard forces led by Shō Motosuke advanced to the area of Mount Mitō, the Ukita vanguard forces led by Akashi Ukikatsu, Togawa Hideyasu, Osafune Sadachika, and Ukita Tadaie took advantage of their position atop the mountain to rain fire from their arquebuses down on the troops, triggering panic and retreat. In the midst of the chaos, Motosuke and fifty soldiers held their ground, and, resolved to die in battle, attacked the forces under Nobuhara Tosa-no-kami. The forces under Tosa-no-kami initially tried to flee until another unit led by Ukita Tadaie attacked the forces under Motosuke from the flank. Having seen the banner of the Ukita, Motosuke made another valiant attempt to attack the enemy, but owing to their weakened position, was forced to commence a retreat, during which he was killed by Nose Yoriyoshi. Nevertheless, there are historical records that, after this battle, Shō Motosuke served under the command of the Mōri, and participated in actions in Kyūshū and elsewhere, so news of his death in this battle may have been erroneous or misinformation spread by the Ukita.
Rout of the middle division of the Mimura army
After Ishikawa Hisamoto, the commander of the middle division, heard about the route of the vanguard forces following the fall of Myōsenji Castle, he had to change his plans so he called upon a clan elder named Nakashima Kaga-no-kami for a war council. Kaga-no-kami proposed setting-up a base on the western shore of the Asahi River from which to launch attacks against Ukita forces crossing the river. Hisamoto agreed with the proposal, but other clan elders disagreed, so they held a separate deliberation. While Hisamoto pondered the strategy, forces from the main contingent of the Ukita comprised of units of the Kōmoto, the Tsushima, as well as Hanabusa Motohide, split-up in three directions and attacked. This led Hisamoto to reinforce his defenses on the main road through the village of Oharashima.
Soldiers in the main division of the Ukita shot their arquebuses in a frontal attack on the forward units of Ishikawa forces. Units of the Kōmoto and Hanabusa pressed troops toward each side of the defenders, aiming for a suitable time to launch a pincer attack. Subject to attack from three directions, the Ishikawa forces fell into disarray, and soon after re-grouping began to flee in defeat toward Nakashima Castle. At this stage, Nakashima Kaga-no-kami and many other commanders were killed in action.
The Ukita forces chased their opponents to near the village of Hachiman. The Ishikawa forces reassembled and attempted to counterattack, where the momentum of victory caused the Ukita to over-extend and suffer significant losses. This turn of events led to a rout of the Ukita instead; however, having incurred major casualties on their own side, Hisamoto chose not to chase the enemy and withdrew from the battle.
The main division of the Mimura vs. the main division of the Ukita
While passing through near the village of Shinogoze, Mimura Motochika saw flames coming from Myōzenji Castle, and concluded that the castle must have fallen. After receiving news that soldiers from the vanguard and middle divisions were routed, the troops fell silent. A majority of the Mimura forces were members from local families of influence who gathered when called by Motochika in the same manner as for a former sengoku daimyō. When it became apparent that they had lost the battle, the soldiers began to depart from the rear guard. The area, however, had small streams everywhere, so many soldiers and their horses fell into the water, triggering a scene of chaos.
In the midst of this confusion, a group of hatamoto charged with maintaining order among the troops headed south with the aim of a final showdown against Ukita Naoie to avenge their lord. Upon learning of these developments, Naoie ordered commanders and their troops who were taking a temporary respite from battle to come down from Mount Komaru. With Akashi Yukikatsu and Oka Ietoshi leading the vanguard, the men set-up a camp.
After Motochika observed the Ukita banner, he committed to a battle of revenge and vigorously attacked. The smaller contingent led by Yukikatsu and Ietoshi was soon cut down, but then troops in the rear guard including the Togawa, the Osafune, the Ukita, and the Nobuhara launched a pincer attack against the Mimura forces. Although driven by desire for revenge, the Mimura could not withstand attacks from three directions, and fell into chaos. Having resolved to die in battle, Motochika planned to make a final thrust forward into the Ukita forces, but, upon the protestations of several of his commanders, withdrew instead. Owing to their inferior numbers, the Ukita forces did not give chase to their opponents.
The post-battle situation
This was the only battle for Ukita Naoie when he charged the enemy in a frontal attack and is regarded as the most impressive major victory that he achieved. The ingenious battle strategy and tactics became legendary in the surrounding provinces. In this conflict, the Ukita clan expelled the Mimura who were their most powerful enemy from the western portion of Bizen Province. BY garnering control of Fukuoka which was the home of prominent metal works for the manufacture of arquebuses, the Uragami clan and their retainers achieved a greater degree of autonomy and voice in affairs. Thereafter, the Ukita clan attained the position of a sengoku daimyō in Bizen notwithstanding their status as a retainer of the Uragami.