Yamana Suketoyo


Yamana Clan

Sengoku Daimyō

Tajima Province

Lifespan:  Eishō 8 (1511) to 5/21 of Tenshō 8 (1580)

Name Changes:  Tsuguhiro → Suketoyo → Sōsen (monk’s name)

Other Names:  Akihiro

Rank:  bushō, sengoku daimyō

Title:  Junior Fifth Rank (Lower) and Chief of Outer Palace Guards of the Right Division

Clan:  Yamana

Lord:  Ashikaga Yoshiharu → Ashikaga Yoshiteru → Ashikaga Yoshihide → Ashikaga Yoshiaki

Father:  Yamana Okitoyo

Adoptive Father:  Yamana Nobutoyo

Siblings:  Suketoyo, Toyosada, Toyohiro (?)

Wife: [Formal] Daughter of Isshiki Yoshiari

Children:  Munetoyo, Yoshichika, Akihiro

Yamana Suketoyo served as a bushō and sengoku daimyō during the Sengoku period.  He was the military governor of Tajima Province.

First half of his life

In 1511, Suketoyo was born as the second son of Yamana Okitoyo.  Initially, he was known as Tsuguhiro.  Suketoyo became the adopted successor of his uncle, Yamana Nobutoyo, who served as the military governor of Tajima.  Upon the death of Nobutoyo in 1528, Suketoyo inherited the headship of the main branch of the Yamana clan.  He adopted a character used in the name of members of the family since Yamana Mochitoyo (Sōzen) and is deemed to have changed his name to Suketoyo at this time.

His adoptive father, Nobutoyo, joined forces with Hosokawa Takakuni in opposition to Hosokawa Harumoto, but Suketoyo sided with Harumoto.  It appears that Suketoyo moved to support Harumoto who stood in opposition to the rapidly ascending Amago clan aligned with Takakuni.  In 1531, Takakuni was subsequently eliminated in a clash known as the Collapse at Daimotsu.  In 1540, Suketoyo was invested with the title of Junior Fifth Rank (Lower) and Chief of Outer Palace Guards for the Right Division.  Around this time, traces can be seen of Suketoyo joining Harumoto, Rokkaku Sadayori, and Hosokawa Mototsune to travel to Kyōto to serve in the bakufu administration.

In 1542, silver deposits were discovered in Ikuno.  To manage silver mining operations on Mount Ikuno, Suketoyo engaged in a major renovation of Ikuno Castle built by his ancestors.  Originally, it was a solitary mountain castle but he built residences in the foothills below the castle enabling the castle to serve as an administrative center into the early Modern period.

For generations, the Yamana clan was devoted to the Rinzai sect of Zen Buddhism.  Suketoyo followed this tradition, building the Ginzan Temple in the foothills below Ikuno Castle.  The Izushi District was the only portion of Tajima that he fully controlled.  Ōtagaki Terunobu of the Asago District, Yagi Toyonobu of the Yabu District, Kakiya Mitsunari of the Keta District, Tainoshō Koreyoshi of the Kinosaki District, Kakiya Toyotsugu of the Mikumi District, Takimi Toyotaka of the Shitsumi District, and Enya Takakiyo of the Futakata District vied against one another for influence.

During this period, the Yamana clan was split between the families of the military governors of Tajima and Inaba provinces.  Aiming to unify the clan, in 1548, Suketoyo killed Yamana Nobumichi, the military governor of Inaba.  As the new landlord, Suketoyo appointed his younger brother, Yamana Toyosada, to serve as the deputy military governor of Inaba to stabilize the province.  The Yamana had served for generations as the military governors of Inaba, Hōki, and Bingo.  In 1552, Ashikaga Yoshiteru, thirteenth shōgun of the Muromachi bakufu, appointed Amago Haruhisa to be the governor-general of the eight western provinces of Izumo, Oki, Inaba, Hōki, Mimasaka, Bizen, Bitchū, and Bingo, as well as an official of the bakufu.  This reflected a decline in the capacity of Suketoyo to influence the central authorities in the wake of the fall of Harumoto.  Meanwhile, there was a movement among bushō such as Wachi Masaharu to back Suketoyo as the provincial lord and resist the Amago clan but even the Wachi clan approached the Ōuchi and Mōri clans in recognition of their military power.

In 1560, after the death of his younger brother, Toyosada, Suketoyo dispatched his own eldest son, Yamana Munetoyo, to serve as the deputy military governor.  In the fifth month of 1561, Munetoyo died at the age of eighteen so Suketoyo appointed his nephew (Toyosada’s orphan, Yamana Toyokazu) as the deputy military governor and delegated responsibility for governance to him.  Following the death of Munetoyo, Suketoyo’s second son, Ujihiro (later known as Yamana Yoshichika) became his designated heir.  He then expanded Konosumiyama Castle inherited from his father to serve as the main base of the Yamana clan and headquarters for the military governor of Tajima.  Suketoyo then strengthened his defenses by constructing a large citadel reflective of the Sengoku period.

In 1564, Suketoyo attacked Takeda Takanobu, a rebellious kokujin, or provincial landowner, in Inaba Province but failed.  In 1569, after the Amago Revival Army led by Amago Katsuhisa and Yamanaka Yukimori invaded Izumo Province, Suketoyo supported them and fought against Mōri Motonari.

In 1569, Suketoyo was attacked by Kinoshita Hideyoshi (later known as Toyotomi Hideyoshi), a retainer of the Oda clan.  This preceded a deterioration in relations between the Oda and Mōri clans.  Mōri Motonari negotiated via Asayama Nichijō with Nobunaga.  An agreement was reached by which the provincial border of Tajima and Inaba would be recognized as the borderline between the spheres of influence of the Oda and Mōri clans.

As a result, Suketoyo departed from his base at Konosumiyama Castle and built the more robust Arikoyama Castle, moved the headquarters of the military governor of Tajima and defended the site.  Nevertheless, after incurring violent assaults by the Kinoshita army, Suketoyo was ousted from his territory and fled to Sakai in Izumi Province.

Second half of his life

Through the offices of Imai Sōkyū, a wealthy merchant from Sakai, Suketoyo met directly with Oda Nobunaga.  Going forward, he pledged to provide forces to the Oda army advancing west, and, in exchange, obtained recognition of his rights to his territory in the Izushi District of Tajima.  In 1570, he returned to his position as the lord of Arikoyama Castle.  Below the castle, he built a residence for regular use and developed the surrounding town.  This became the foundation for the evolution of the town of Izushi in later years.

Thereafter, Suketoyo cooperated with Amago Katsuhisa (who also aligned with Nobunaga) and fought on behalf of the Oda against the rival Mōri clan.

Later in 1570, Suketoyo was attacked by Akai Tadaie from Tanba Province, leading to the occupation by the enemy of Takeda and Konosumiyama castles.  In 1571, Suketoyo received reinforcements from the Oda to attack the Hikami District of Tanba.

In 1572, Suketoyo fought against Takeda Takanobu and Yamanaka Yukimori who sided with the Mōri.  That same year, his lineal heir, Yamana Ujihiro, received one of the characters from the name of Ashikaga Yoshiaki (the fifteenth shōgun of the Muromachi bakufu) and adopted the name of Akitoyo, later changing again to Yoshichika.

In the eleventh month of 1575, Suketoyo along with reinforcements from his third son, Yamana Akihiro, went from Takeda Castle to the Hikami District and, with Akechi Mitsuhide, a senior retainer of Nobunaga, attacked.  These forces, however, we defeated by an army led by Hatano Hideharu who came in support of Ogino Naomasa of Kuroi Castle after which Mitsuhide returned to his home base at Sakamoto Castle in Ōmi Province.

In the tenth month of 1574, Yamana Toyokuni reconciled with the Mōri clan while one of Suketoyo’s senior retainers, Ōtagaki Terunobu, settled with Kikkawa Motoharu, a retainer of the Mōri.  Upon solicitation from Toyokuni and Terunobu, in the first month of 1575, Suketoyo also settled and formed an alliance with the Mōri clan.  The alliance between the Yamana and the Mōri (between Aki and Tajima provinces) was intended to resist Amago Katsuhisa and the remnants of the Amago clan including Yamanaka Yukimori along with the Mimura and Uragami clans who joined the campaign in opposition to the Mōri upon the invitation of Katsuhisa.  The alliance between the Yamana and the Mōri, however, was not intended for a final showdown against the Oda clan.  Although the attack by Ogino Naomasa against Terunobu at Takeda Castle occurred after Terunobu joined forces with the Mōri, Terunobu was regarded as belonging to the Oda faction.

From 1575, as an outcome of opposing the Mōri, Uragami Munekage (who had been ousted from Bizen), along with Amago Katsuhisa and Yamanaka Yukimori and his followers in the Amago Revival Army turned to Nobunaga for support whereupon relations between the Mōri and the Oda rapidly declined.  In 1576, the Yamana clan and senior retainers including the Kakiya and Ōtagaki clans severed ties with the Oda and pursued a path to strengthen their alliance with the Mōri.  Suketoyo and Toyokuni were disappointed after the Oda administration denied them positions of governor-general of Tajima and Inaba provinces.  The Ōtagaki clan came into conflict with the Oda over rights to silver mines while the Kakiya clan moved in support of the Mōri based on economic ties in the form of marine transport for the territory of the Mōri.  Akamatsu Norifusa and Munekage came under the command of the Oda.  Relations between the Akamatsu (including the Uragami as their senior retainers) and Yamana clans had been strained since the time of the Kakitsu Disturbance in 1441 and may have influenced their decisions.

Although upset with these developments, Nobunaga did not take immediate action because he placed the highest priority on pacifying Harima.  While another deployment to Tajima began in the eleventh month of 1577, Hashiba Hideyoshi operated under orders from Nobunaga to bring stability by ruthlessly pacifying the province.  Thereafter, Kakiya Toyotsugu, supported by reinforcements from the Mōri army, attacked Kakiya Mitsunari who was aligned with the Oda so that the status of the conflict in Tajima tilted in favor of the Mōri.  Suketoyo, however, was not always in sync with the Mōri army and conflict persisted between the Mōri and Oda factions in Tajima.

In the sixth month of 1579, Mitsuhide toppled the base of Hideharu at Yakami Castle.  Around this time, after Ukita Naoie (who governed Bizen Province) surrendered to Nobunaga, the situation suddenly turned in favor of the Oda clan.

On 5/21 of Tenshō 8 (1580), after a huge contingent of Oda forces led by Hideyoshi surrounded Amakoyama Castle, Suketoyo was forced to vacate the premises and died of illness shortly thereafter.  He was seventy years old.

Suketoyo’s third son, Yamana Akihiro, had differences of opinion with Suketoyo so prior to vacating the castle, he fled to a neighboring province for assistance.  Later, he was promoted by Hideyoshi and became an umamawari, or member of the elite cavalry division.  Suketoyo’s second son, Yamana Yoshichika, was said to have fled to Shinano Province and his descendants are there.