Battle of Fukai

深井の合戦

Hosokawa Clan

Izumi Province

Hosokawa Clan

Date:  7/13 of Eishō 8 (1511)

Location:  Fukai Castle near the harbor town of Sakai in Izumi Province, south of Ōsaka

Synopsis:  This was one of the battles during the prolonged succession struggle between Hosokawa Sumimoto and Hosokawa Takakuni to become head of the Hosokawa-Keichō family.  In this event, Sumimoto sent forces from Awa Province to launch attacks near Sakai.  Takakuni responded by dispatching an army to confront them at Fukai Castle.  Upon breaching the castle, the attacking forces learned the premises had been vacated and were then slaughtered while attempting to exit.

Commander: Hosokawa Masakata

Forces:  Hosokawa Mototsune, Yamanaka Tametoshi, Hatakeyama Takakuni, Yusa Yorimori, units of irregulars

Participants:  7,000 to 8,000

Casualties: Unknown

Commander: Unknown

Forces: Members of the Ikeda, the Miyake, the Ibaraki, the Itami, the Aiu, the Fukui, the Ōta, the Irie, and the Takatsuki clans

Participants:  20,000

Casualties:  300

The Battle of Fukai occurred on 7/13 of Eishō 8 (1511) at Fukai Castle in the harbor town of Sakai in Izumi Province, south of Ōsaka. 

This represented one event in a prolonged series of military clashes between rivals within the Hosokawa clan that occurred between 1509 and 1531, known as the Conflict between the Hosokawa (Ryō-Hosokawa no ran).  These events comprised the military component of a broader succession struggle between the adopted sons of Hosokawa Masamoto. Masamoto was an influential deputy shōgun, with de facto power over the bakufu. However, tensions arose from his choice of a successor, leading to his assassination in 1507, known as the Lord Hosokawa Incident (Hosokawa-dono no hen).  Intertwined with this struggle existed a rivalry between Ashikaga Yoshitane and Ashikaga Yoshizumi to serve as shōgun, all occurring in the midst of a decline in the capacity of the Muromachi bakufu to exercise authority in the capital of Kyōto and beyond.  This multi-faceted struggle is known as the Eishō Disturbance (Eishō no sakuran), commencing from the time of Masamoto’s assassination in 1507 until the defeat of Hosokawa Takakuni by Hosokawa Harumoto at the Collapse at Daimotsu (Daimotsu kuzure) in 1531.

There are very limited sources of information concerning the history of Fukai Castle other than this battle.

Prelude

In 1509, after the Battle of Nyoigatake, Hosokawa Sumimoto returned to Awa Province, whereupon he sought to devise a military strategy to return to Kyōto and enable Ashikaga Yoshizumi to reclaim his position as shōgun.  On 7/7 of 1511, he assigned family members – Hosokawa Masakata and Hosokawa Mototsune (the military governor of Izumi Province) – to serve as the lead commanders of an army that landed on the shoreline of Sakai.  The forces launched an initial attack against Tennōji Castle.  Then, Yamanaka Tametoshi, Hatakeyama Takakuni, and Yusa Nobumori, along with a group of irregulars, converged to set-up positions near Fukai Castle.  The army led by Masakata totaled seven to eight thousand men.

Upon hearing of this news, Hosokawa Takakuni, a rival of Sumimoto, ordered kunishū, or families of local influence, in Settsu Province to attack them, and quickly took action.  This led to the formation of an army of 20,000 men comprised of members of the Ikeda, the Itami, the Miyake, the Ibaraki, the Aiu, the Fukui, the Ōta, the Irie, and the Takatsuki clans, establishing bases at the Nishimura and Higashimura fortresses.

Course of events

The battle commenced on 7/13 after Takakuni sent his vanguard forces toward Fukai Castle.  After invading the castle, it became known that no one remained.  The exits were closed and the soldiers trapped inside the complex.  As the invaders sought to escape, units under Hosokawa Masakata descended upon the exits and engaged in violent clashes with those attempting to exit the castle.  Takakuni’s men fought valiantly, but were all cut down, with over 300 commanders and soldiers slayed in the battle.

Aftermath

Survivors among Takakuni’s army fled to Sakai, while Masakata seized the opportunity to attack Nakajima Castle that same day.  This led to the ensuing Battle at Funaokayama.