
Ōtomo Yoshishige came from a noble lineage, being the eldest son of Ōtomo Yoshiaki, the ruler of Funai Province. The roots of the Ōtomo family traced back to Fujiwara Hidesato, the adopted son of Nakahara Chikayoshi. Fujiwara served Minamoto Yoritomo during the Genpei War and took part in battles in Mutsu Province in 1189. In 1193, he was appointed shugo of Buzen and Bungo Provinces, after which he adopted a new surname—Ōtomo.
Rise of Ōtomo Yoshishige
In 1550, Ōtomo Yoshiaki was killed by his vassal Tsukuni Mimasaka. After his death, Ōtomo Yoshishige became the twenty-first head of the clan. He showed natural leadership and began expanding the clan’s lands on Kyushu. In 1551, he suppressed the rebellion of Kikuchi Yoshimune in Higo Province. In 1557, he invaded Chikuzen Province and subjugated Akizuki Kiyotane. In 1559, he organized a successful attack that allowed the clan to retake Moji Castle, previously seized by the Mori clan. However, Mori forces soon recaptured the castle, and a later attempt in 1561, even with Portuguese naval support, failed.
The Adoption of the Name Sōrin and Early Alliances
In 1562, Yoshishige adopted the name Sōrin, by which he is best known. That same year he formed an alliance with the Mori clan’s enemies—the Amako clan—and launched an offensive against Mori fortifications in Buzen Province. A peace agreement was reached thanks to the mediation of Shogun Ashikaga Yoshiteru. According to the terms, one of Sōrin’s daughters was to marry Mori Terumoto, though it remains unclear whether the marriage ever took place.
Confrontation with Ryūzōji and Expansion of Influence
In 1568, Ōtomo began a war against the Ryūzōji clan of Hizen Province, a move that in practice struck at Mori influence. Yet Ōtomo vassal Hetsugi Akitsura was defeated by Mori forces in the 1569 Battle of Tatarahama, losing Tachibana Castle. In response, Sōrin attacked Mori positions in Buzen, forcing them to retreat. After these events, Sōrin effectively controlled Bungo, most of Buzen, Chikuzen, Chikugo, and held significant influence in Higo and Hizen. Ōtomo banners even flew over castles in Iyo Province, captured from the Kōno clan. His army became known as “Ōtomo Shichikakoku no Zei”—the Army of the Seven Provinces.
Internal Weaknesses of the Clan
Despite his power on paper, Sōrin remained vulnerable. The main obstacles to his ambitions were the lack of unity among his vassals and the threat posed by the strong Shimazu clan. Some lineages, such as Tachibana and Tamura, maintained significant independence and were not true vassals in the full sense, hindering Sōrin’s ability to enforce total control like a successful Sengoku-era daimyo.
Christianity and Internal Conflict
In 1551, Sōrin welcomed Francis Xavier and permitted the establishment of a Jesuit mission in Bungo. He treated Christian missionaries favorably—perhaps due to the weapons and trade opportunities Europeans offered, though personal influence of the religion cannot be dismissed. However, his support for Christianity sparked discontent: his wife strongly opposed it, and many vassals were angered by missionary activities, especially the desecration of Buddhist and Shinto temples. Despite this, Sōrin continued to support the missionaries and in 1575 had his son baptized. In 1578, he divorced his wife and was baptized himself, taking the Christian name Francisco. Two years earlier he had transferred power to his son Yoshimune, who bore the Christian name Constantine.
Invasion of Hyūga and the Shimazu Conflict
The situation shifted when the Shimazu clan destroyed the Itō clan, forcing Itō Yoshisuke to seek refuge with Ōtomo. Yoshimune decided to launch an invasion of Hyūga Province before the Shimazu could unite their forces. Eager to prove himself as clan leader, he ignored warnings from his vassals that such a campaign would provoke other enemies. He raised an army of about forty thousand warriors and marched into Hyūga. Sōrin accompanied him, planning to found a new Christian city there.
Early Victories and Fatal Mistakes
Their first obstacle was Matsuo Castle, commanded by Tsuchimochi Chikanari—a capable general who had once served the Itō but later defected to the Shimazu. The Ōtomo army defeated Tsuchimochi and annexed his lands, where Sōrin and Yoshimune began destroying local Buddhist and Shinto temples, provoking anger among locals and their own vassals.
The main forces were placed under Tawara Chikataka, Sōrin’s half-brother. Tawara crossed the Omaru River and stopped at Taka Castle, defended by three thousand warriors under the experienced Shimazu Iehisa. Tawara made a critical mistake: he chose to bypass the castle, leaving only a small blocking force, and underestimated the Shimazu commanders. Meanwhile, Shimazu Yoshihisa executed a series of maneuvers that culminated in the Battle of Mimigawa. The battle ended in a disastrous defeat for the Ōtomo: thousands were killed, thousands fled.
Decline of the Ōtomo Clan
Sōrin and his son retreated to Bungo in deep despair. Fortune had abandoned the clan. The next year they lost Chikugo to the Ryūzōji. A new rebellion by Akizuki Tanezane broke out. Unrest also spread in Bungo due to continued support for Christian missions. The Ōtomo position became so weak that the Shimazu offered a cease-fire, which the clan accepted immediately. This allowed the Shimazu to turn their focus toward their more dangerous enemy—Ryūzōji Takanobu.
Last Hope: Alliance with Hideyoshi
In 1586, the Ōtomo’s misfortunes reached their peak. After the death of Ryūzōji Takanobu in battle with the Shimazu, Yoshihisa turned his attention to Bungo. In May, Sōrin left his residence in Usuki and traveled to Osaka to plead with Toyotomi Hideyoshi for protection. Hideyoshi already planned to conquer Kyushu, and Sōrin’s request provided the perfect justification.
In December, the first corps of Hideyoshi’s army landed on Kyushu and joined forces with Ōtomo Yoshimune. Although the combined forces were defeated in the Battle of Hetsugigawa, Hideyoshi’s massive main army, following close behind, drove the Shimazu back to Satsuma.
The End of Clan Independence
Sōrin died soon after the defeat of the Shimazu. Although the Ōtomo lands were once again safe, the clan lost its independence forever.
See also
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Yamagata Masakage

Masakage was one of Takeda Shingen’s most loyal and capable commanders. He was included in the famous list of the “Twenty-Four Generals of Takeda Shingen” and also belonged to the inner circle of four especially trusted warlords known as the Shitennō.
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Yagyu Munenori

Yagyū Munenori began his service under Tokugawa Ieyasu while his father, Yagyū Muneyoshi, was still at his side. In 1600, Munenori took part in the decisive Battle of Sekigahara. As early as 1601, he was appointed a kenjutsu instructor to Tokugawa Hidetada, Ieyasu’s son, who later became the second shogun of the Tokugawa clan.
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Yagyu Muneyoshi

A samurai from Yamato Province, he was born into a family that had been defeated in its struggle against the Tsutsui clan. Muneyoshi first took part in battle at the age of sixteen. Due to circumstances beyond his control, he was forced to enter the service of the Tsutsui house and later served Miyoshi Tōkei. He subsequently came under the command of Matsunaga Hisahide and in time became a vassal first of Oda and later of Toyotomi.
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Endo Naozune

Naozune served under Azai Nagamasa and was one of the clan’s leading vassals, renowned for his bravery and determination. He accompanied Nagamasa during his first meeting with Oda Nobunaga and at that time asked for permission to kill Nobunaga, fearing him as an extremely dangerous man; however, Nagamasa did not grant this request.
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Hosokawa Sumimoto

Sumimoto came from the Hosokawa clan: he was the biological son of Hosokawa Yoshiharu and at the same time the adopted son of Hosokawa Masamoto, the heir of Hosokawa Katsumoto, one of the principal instigators of the Ōnin War. Masamoto was homosexual, never married, and had no children of his own. At first he adopted Sumiyuki, a scion of the aristocratic Kujō family, but this choice provoked dissatisfaction and sharp criticism from the senior vassals of the Hosokawa house. As a result, Masamoto changed his decision and proclaimed Sumimoto as his heir, a representative of a collateral branch of the Hosokawa clan that had long been based in Awa Province on the island of Shikoku. Almost immediately after this, the boy became entangled in a complex and bitter web of political intrigue.
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Honda Masanobu

Masanobu initially belonged to the retinue of Tokugawa Ieyasu, but later entered the service of Sakai Shōgen, a daimyo and priest from Ueno. This shift automatically made him an enemy of Ieyasu, who was engaged in conflict with the Ikkō-ikki movement in Mikawa Province. After the Ikkō-ikki were defeated in 1564, Masanobu was forced to flee, but in time he returned and once again entered Ieyasu’s service. He did not gain fame as a military commander due to a wound sustained in his youth; nevertheless, over the following fifty years he consistently remained loyal to Ieyasu.
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Honda Masazumi

Masazumi was the eldest son of Honda Masanobu. From a young age, he served Tokugawa Ieyasu alongside his father, taking part in the affairs of the Tokugawa house and gradually gaining experience in both military and administrative matters. At the decisive Battle of Sekigahara in 1600, Masazumi was part of the core Tokugawa forces, a clear sign of the high level of trust Ieyasu placed in him. After the campaign ended, he was given a highly sensitive assignment—serving in the guard of the defeated Ishida Mitsunari, one of Tokugawa’s principal enemies—an obligation that required exceptional reliability and caution.
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Hojo Shigetoki

Hōjō Shigetoki, the third son of Hōjō Yoshitoki, was still very young—only five years old—when his grandfather Tokimasa became the first member of the Hōjō clan to assume the position of shogunal regent.
