The Battle of Funaokayama

Background — The Outbreak of the Ryō-Hosokawa War

Funaokayama is a small hill 111.7 meters above sea level in Kita Ward, Kyoto. It lies directly north of Suzaku Avenue (present-day Senbon Street), the central axis of Heian-kyō, and is a strategic height. In the Ōnin War of Ōnin 1 (1467), western-army commanders including Yamana Noriyuki fortified themselves on this hill by building Funaokayama Castle, and the area came to be called "Nishijin," which is the origin of that name. Because it commanded a view of the Kyoto basin, Funaokayama became a place where armies were deployed during each of the civil disturbances in the Kinai region.

The origins of the Battle of Funaokayama trace back to the "Ryō-Hosokawa War," the struggle over the headship of the Hosokawa Keichō house. In Meiō 2 (1493), kanrei Hosokawa Masamoto staged a coup known as the Meiō Incident, expelling shogun Ashikaga Yoshiki (later Yoshitane) and installing Ashikaga Yoshizumi as the new shogun, thereby seizing real control of shogunal governance. However, Masamoto had no biological son. He had taken in three adopted heirs, Hosokawa Sumiyuki, Hosokawa Sumimoto, and Hosokawa Takakuni, which planted the seeds of conflict as the adopted heirs opposed one another over the succession. Of these, Takakuni was born as a son of Hosokawa Masaharu of the Yashū-ke, a branch of the Hosokawa clan, and became an adopted son of Masamoto in early childhood. He had a family-rank origin different from that of Sumiyuki and Sumimoto.

In the 6th month of Eishō 4 (1507), on the 23rd day, Masamoto was assassinated by Sumiyuki's faction in what became known as the Eishō Disturbance. Hosokawa Sumimoto, who had fled to Ōmi, later regained his strength, retook Kyoto, and expelled Sumiyuki, securing the headship of the house. This series of internal strife made the headship of the Hosokawa Keichō house, the greatest power supporting the foundations of the Muromachi shogunate, repeatedly contested among three adopted heirs. It became a fundamental cause that kept the politics of the Kinai region unstable for more than ten years afterward.

The Road to War

Meanwhile, former shogun Ashikaga Yoshiki (Yoshitane), who had been expelled in the Meiō Incident, had taken refuge in the Chūgoku region under the protection of the powerful Suō daimyō Ōuchi Yoshioki. Yoshioki was known as the strongest figure in western Japan. As head of the Ōuchi clan, which controlled the Japan-Ming trade, he stood in the position of protecting the former shogun in exile. In Eishō 5 (1508), Yoshitane set out for Kyoto accompanied by Yoshioki. When Hosokawa Takakuni rose in arms in response, the forces of Yoshizumi and Sumimoto could not hold the capital and were routed. Yoshitane was restored as shogun, and a system was established in which Takakuni, as kanrei, took the lead in shogunal governance. Yoshitane was expelled once in the Meiō Incident, and after his restoration in Eishō 5 he would be driven from Kyoto again in Daiei 1 (1521) due to conflict with Takakuni. His career was unusual even among the successive shoguns of the Muromachi shogunate.

However, Sumimoto's side did not stop resisting. In Eishō 8 (1511), seeking to recover from its inferior position, it turned to counterattack. Sumimoto's side won successive victories at the Battle of Fukai in Izumi Province and the Battle of Ashiyagawara in Settsu Province, and at one point it retook Kyoto. Yoshitane and Takakuni fled to Tanba, and the situation in the capital once again became fluid. During this period, Yoshitane and Takakuni's side was forced onto the defensive in the Settsu and Kawachi areas. It is thought that for a certain period, the environs of Kyoto remained under the effective control of Sumimoto's side.

The Standoff and the Defection of the Rokkaku

Driven from Kyoto, Takakuni and Yoshioki's side regrouped and watched for an opportunity to strike back. During this period, Rokkaku Takayori of Ōmi, who had been aligned with Sumimoto's side, suddenly defected to Yoshitane's side. The Rokkaku clan possessed one of the largest military forces in Ōmi, and its defection dealt a major blow to Sumimoto's strategy. Compounding this, former shogun Ashikaga Yoshizumi, whom Sumimoto's side had installed, died of illness in despair. Sumimoto's side gradually lost the initiative in the conflict. In response to these changes, Takakuni and Yoshioki resolved on a major offensive to retake Kyoto, and the two armies were to settle the outcome at Funaokayama in Yamashiro Province (present-day Kita Ward, Kyoto).

The Course of the Battle

From the 23rd to the 24th day of the 8th month of Eishō 8 (September 15–16, 1511), the two armies clashed at Funaokayama. Sumimoto's side, with Hosokawa Masakata as commanding general and joined by Hosokawa Mototsune and Yamanaka Tametoshi, deployed on Funaokayama and took up a defensive posture. Masakata, Mototsune, and Yamanaka Tametoshi were all warriors in a position resembling direct vassals of the shogunate, and they belonged to the side of Ashikaga Yoshizumi and Hosokawa Sumimoto. For Sumimoto's side, Masakata was a commander who could be called a trump card. Their combined strength was Masakata's two thousand, Mototsune's one thousand, and Yamanaka Tametoshi's three thousand, totaling roughly six thousand. This was overwhelmingly outmatched by the more than twenty thousand troops fielded by Takakuni and Yoshioki, and the disparity in strength was clear.

When Ōuchi Yoshioki's army carried out a night raid on Funaokayama, the outnumbered Sumimoto's side could not withstand it and collapsed entirely. Commanding general Hosokawa Masakata died in the chaos of battle, and Yusa Insō, among others, also took his own life. Sumimoto's side suffered heavy losses. The Ōuchi army, which had come on campaign from Suō and Nagato, effectively used the tactic of a night attack to make the most of its numerical superiority, even though it was fighting in Yamashiro Province far from its home territory.

Result — Sumimoto's Flight and the Recovery of Kyoto

The crushing defeat at Funaokayama forced Hosokawa Sumimoto to flee to his home base in Awa Province (present-day Tokushima Prefecture). As a result, Kyoto returned to the hands of Ashikaga Yoshitane and Hosokawa Takakuni, and Yoshitane's position as shogun and Takakuni's position as kanrei were stabilized for the time being. The disparity in strength between the two armies was overwhelming, with Takakuni and Yoshioki's side at more than twenty thousand against Sumimoto's side at roughly six thousand. The Battle of Funaokayama is recorded as one of the largest pitched battles of the Ryō-Hosokawa War.

Aftermath — The Later Fates of Sumimoto and Ōuchi Yoshioki

Even after the defeat at Funaokayama, Hosokawa Sumimoto continued to resist. In Eishō 17 (1520), he briefly recovered Kyoto. However, his chief retainer Miyoshi Yukinaga was killed at the Battle of Tōji-in, and Sumimoto himself died in the turmoil that followed later that same year. Meanwhile, Ōuchi Yoshioki, who had aided Takakuni's side in the battle, remained in the capital for a certain period to support the shogunate. In Eishō 15 (1518), however, he returned to his home province of Suō in response to unrest stirred up by the Amago clan of Izumo and the Aki Takeda clan. Yoshioki never again went up to Kyoto, and he died of illness in the 12th month of Kyōroku 1 (early 1529). The return of the Ōuchi army to its home province, which had played a decisive role in Takakuni's victory at Funaokayama, transformed Takakuni's position in Kyoto thereafter into one he had to maintain without the strong backing of the Ōuchi clan.

Takakuni's Downfall and the Continuation of the Ryō-Hosokawa War

Having consolidated his hold on the Hosokawa Keichō house through his victory at Funaokayama, Takakuni maintained his position as kanrei leading shogunal governance for nearly ten years afterward. The political situation that followed, however, was not necessarily secure. Takakuni eventually came into conflict with shogun Ashikaga Yoshitane. In Daiei 1 (1521), he expelled Yoshitane and installed Ashikaga Yoshiharu as the new shogun. Then conflict with Sumimoto's son, Hosokawa Harumoto, grew sharper. Takakuni was defeated at the Battle of Katsuragawara in Daiei 7 (1527), and he was ultimately driven to suicide after the defeat at Ōmono Kuzure in Kyōroku 4 (1531).

The Battle of Funaokayama is positioned as the battle in which the Takakuni–Yoshioki side achieved its clearest victory in the Ryō-Hosokawa War, which continued intermittently for nearly half a century over the headship of the Hosokawa Keichō house and the initiative in the shogunate. However, this victory did not mean the end of the Ryō-Hosokawa War itself. The victor, Takakuni, would himself meet a violent death at the end of his struggle with Sumimoto's bloodline. In this sense, the battle symbolizes the complexity and severity of the power struggles surrounding the Hosokawa clan in the early Sengoku period. Today, Kenkun Shrine is enshrined on the summit of Funaokayama, the site of the battle, and the entire mountain has been developed as Funaokayama Park. It conveys the history of this place, which has been the stage of civil unrest in the Kinai region many times since the Ōnin War.