Battle of Shiraikawara
Date: 8/28 of Genki 2 (1571)
Location: The environs of Shiraikawara in the Shimashimo District of Settsu Province
Outcome: Despite being significantly outnumbered and unprepared, Wada Koremasa led the charge against the Araki and Nakagawa allied forces, resulting in near annihiliation.
The Battle of Shiraikawara occurred on 8/28 of Genki 2 (1571) in the environs of Shiraikawara in the Shimashimo District of Settsu Province. The conflict was triggered by Araki Murashige, a retainer of the Ikeda clan, as he sought to expand his power in Settsu and was waged between the allied forces of the Ibaraki and Wada against the allied forces of the Araki and Nakagawa.
Prelude to the hostilities
In 1569, Oda Nobunaga backed Ashikaga Yoshiaki, marched upon Kyōto, and entered Settsu. Miyoshi Nagayasu, the lord of Akutagawayama Castle, fled to Awa Province in Shikoku. After Matsunaga Hisahide joined the Oda army, Takayama Tomoteru, a retainer of Hisahide, followed suit. In 1568, Wada Koremasa, a direct retainer of the Muromachi bakufu who was recently selected to serve as one of the Three Military Governors of Settsu, was assigned Akutagawayama Castle, and quickly rose from the status of a kokujin, or provincial landowner, to a sengoku daimyō.
In the early Sengoku period after the Eishō Disturbance, Settsu witnessed continuous battles. Although, after Nobunaga’s march upon Kyōto, the province was gradually pacified, as of this time it had not been unified. In the eighth month of 1568, the allied forces of Ibaraki Shigetomo and Itami Chikaoki fought against the army of Ikeda Katsumasa at the Battle of Inadera. Thereafter, the situation transformed into a confrontation between Wada Koremasa (a bushō who supported Shigetomo) and the allied forces of Araki Murashige and Nakagawa Kiyohide who ousted Katsumasa from Ikeda Castle. Murashige was supported by Miyoshi Nagayasu who, in the seventh month of 1571, crossed the Seto Inland Sea from Awa Province to make another landing in Settsu for the Battle of Noda and Fukushima Castles. This conflict also represented a power-struggle between the Miyoshi clan and the army of the Muromachi bakufu.
In the eighth month of 1571, the two armies confronted one another across the Shiriakawara Plains along the Saikoku Road. At this time, the allied forces of the Ibaraki and the Wada set-up a position with approximately 500 mounted soldiers in Nukazuka (Mount Mitekura) to the west of the ancient burial mounds of Minohara. Meanwhile, the allied forces of the Araki and Nakagawa established their position with approximately 2,500 mounted soldiers in Mazuka to the north of Kōriyama.
Course of events
Before completing preparations of the battle formations for the Ibaraki and Wada allied armies, Kōri Masanobu, the lord of Kōriyama Castle, headed-out on his own toward the encampment of the Araki and Nakagawa allied forces in a bid to buy additional time to prepare. An army led by Wada Korenaga (Koremasa’s son) trailed behind while Takayama Tomoteru was still in Takatsuki Castle so it is presumed this was an attempt to delay the battle until those additional forces could join. However, the enemy saw through this ploy and responded by initiating hostilities.
In view of these developments, Masanobu advised Koremasa that their forces were outnumbered without prospect for victory, and that, as a general, displays of strength alone were not a reflection of ability, so one should advance or retreat as the circumstances permit, and that a revered general would account for safety when weighing his options. Koremasa, however, completely ignored this advice, leading 200 mounted soldiers to charge the enemy position at Mazuka. Meanwhile, Masanobu rode his renowned horse named kaneyaguro into battle but was killed by a bushō named Yamawaki Gendayū in the allied Araki and Nakagawa army.
Murashige announced that he would award Kurehadai to whomever took the head of Wada Koremasa whereupon Kiyohide in fact killed Koremasa. Kurehadai had a rice yield of 300 to 500 koku, and this land was granted to Kiyohide as a reward. A five-part gravestone representing earth, water, fire, wind and heaven stands in these environs for Koremasa.
In the midst of violent clashes between Kiyohide and Koremasa, the Ibaraki army charged the main encampment of Murashige that had been left shorthanded. However, 2,000 soldiers hiding in the mountain shadows surrounded the Ibaraki forces and deployed 300 arquebusiers to rain fire on the enemy. Despite this barrage, the Ibaraki army continued a valiant fight, and, in the end, Shigetomo himself wounded Murashige but was then killed by Murashige. At this time, Nagai Michitoshi, a retainer of Ashikaga Yoshiaki (the shōgun), also died in battle.
After losing their two commanders, the remnants of the Ibaraki and Wada allied army charged out in the spirit of encountering an honorable death in battle and were almost completely annihilated. At this time, the Shiraikawara was said to be white in name only and flowed blood red.
Once the trailing army led by Wada Korenaga received news of the defeat, the forces returned to Takatsuki Castle and, along with Takayama Tomoteru and Takayama Ukon, strengthened the defenses at the castle.
The allied forces of the Ibaraki and Nakagawa attacked and toppled Ibaraki Castle. After attacking Kōriyama Castle, the army proceeded to surround Takatsuki Castle. Matsunaga Hisahide and Matsunaga Hisamichi (father and son), along with Shinohara Nagafusa (a senior retainer of the Miyoshi family of Awa) joined the siege, while the town below Takatsuki Castle was destroyed after burning for two days and nights.
At the time, there were Christian churches in the environs of Takatsuki Castle under the protection of the Wada and Takayama clans. Observing these developments, the Jesuit missionary, Luís Fróis, dispatched Lorenzo Ryōsai (a Japanese convert to the Jesuit faith) to inform Oda Nobunaga of the situation. After learning of these battles, on 9/9, Nobunaga sent Sakuma Nobumori to warn soldiers in Takatsuki Castle to withdraw. Neither army, however, moved so, on 9/24, Akechi Mitsuhide led 1,000 soldiers to engage in mediation. It was at this stage that Murashige decided to withdraw.
Thereafter, Murashige entered Ikeda Castle while Kiyohide entered Ibaraki Castle. The Miyoshi forces passed through Takatsuki and approached the capital. In the twelfth month of 1572, Miyoshi Yasunaga, Shinohara Jiton, and Shinohara Nasashige each issued prohibitions to the Rikyū-Hachiman Shrine in Ōyamazaki in Yamashiro Province. Meanwhile, Wada Korenaga became the lord of Takatsuki Castle, but came into conflict with Takayama Tadateru and Takayama Ukon (father and son). In the third month of 1573, Korenaga was ousted from Takatsuki Castle by the Tadateru and Ukon with the support of Murashige.
Details of the events leading up to the confrontation between the two armies on 8/28 at Shiraigawara remain uncertain. However, while hostilities broke out before the allied forces of the Ibaraki and Wada could organize sufficient resources, the Araki and Nakagawa forces had already prepared ambushes, so it can be surmised that the battle was initiated by the Araki and Nakagawa.
Owing to this battle, the Three Military Governors of Settsu (Ikeda Katsumasa, Itami Chikaoki, and Wada Koremasa) appointed by Nobunaga lost power, while Araki Murashige, Nakagawa Kiyohide, Takayama Tomoteru, and Takayama Ukon came to the forefront as influential bushō in Settsu. In this respect, the battle marked a transition from the Sengoku period to the early Azuchi-Momoyama period.
A short sword from Nakagawa Kiyohide (said to have been used to kill Koremasa) is kept at the Niiyanimasu-Amaterumitama Shrine in the Shimashimo District of Settsu. This shrine had deteriorated after damage from war incurred in 1527, but, in 1584, was rebuilt by Kiyohide and revered by the Nakagawa family.