
Okubo Tadayo (1532 – October 28, 1594) was a samurai general who served Tokugawa Ieyasu during the Azuchi–Momoyama period and later became the daimyo of Odawara Domain in the early Edo period.
Born in Mikawa Province (modern-day Okazaki, Aichi Prefecture), Tadayo was the eldest son of Okubo Tadakazu, a hereditary retainer of the Tokugawa clan. He was also known by the nickname "Shinjuro." As one of Ieyasu’s sixteen generals, he was entrusted with the defense of Futamata Castle in Totomi Province and played a key role in several major battles.
In 1564, Tadayo fought in the Battle of Azukizaka against the Ikko-ikki in Mikawa Province. During the Battle of Mikatagahara in 1573, he and Amano Yasukage led a small but effective group of Tokugawa foot soldiers and matchlock gunners in a surprise attack on the Takeda camp, causing confusion in their ranks.
In 1574, when Oga Yashiro, a minor Tokugawa official, was discovered plotting with the Takeda clan to overthrow Ieyasu, Tadayo was tasked with eliminating him. Acting on orders from the Okazaki magistrate, Ooka Tadasuke, Tadayo swiftly captured Yashiro, paraded him through Hamamatsu Castle, and then carried out a brutal execution—mutilating him alive with a saw. He also ordered the crucifixion of Yashiro’s wife and children as a warning to other would-be traitors.
Tadayo accompanied Ieyasu in nearly all of his military campaigns, including the Battle of Nagashino in 1575. Following Oda Nobunaga’s assassination in 1582, Ieyasu expanded his control into Shinano Province, assigning Tadayo to oversee operations from Komoro Castle.
After the Battle of Odawara in 1590, Ieyasu was relocated to the Kanto region by Toyotomi Hideyoshi. As a reward for his service, Tadayo was elevated to the rank of daimyo and granted Odawara Domain, with an income of 45,000 koku. He ruled there until his death in 1594, after which his son, Okubo Tadachika, succeeded him.
See also
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Otomo Sorin

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.
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Okudaira Sadamasa

Sadamasa was the son of Okudaira Sadayoshi and took part in several battles under Tokugawa Ieyasu, distinguishing himself in the Battle of Anegawa in 1570, where he took two heads. Around 1572 he was forced to enter the service of the Takeda clan, but after the death of Takeda Shingen in 1573 he returned to Tokugawa, leaving Tsukude Castle together with his men. As a result of this defection, Takeda Katsuyori ordered the execution of Sadamasa’s wife and brother, who were being held as hostages.
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Okubo Tadatika

Tadatika, the son of Okubo Tadayō, entered the service of Tokugawa Ieyasu at the age of eleven, and took his first head in battle when he was sixteen. After the establishment of the Tokugawa shogunate, he was appointed as a rōjū — a senior bakufu official — and was regarded as one of Ieyasu’s most trusted advisors, alongside Honda Masanobu. He is also known for his military chronicle Mikawa Monogatari, which describes Ieyasu’s rise to power and the early years of the Tokugawa shogunate.
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Okubo Nagayasu

Nagayasu was the second son of Okura Nobuyasu, a sarugaku theater actor from the Takeda clan. Takeda Shingen recognized the young man’s potential and took him into service, appointing him as a vassal to his general, Tsuchiya Masatsugu. During this period, Nagayasu changed his family name to Tsuchiya. He was entrusted with developing the Takeda clan’s gold mines as well as handling matters related to taxation.
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Nitta Yoshisada

Nitta Yoshisada was a loyal soldier of Emperor Go-Daigo, who in the 1330s attempted to restore direct imperial rule in Japan. The Nitta family was related to the Ashikaga house and was older in lineage. However, they did not join Minamoto Yoritomo at the start of his war with the Taira, as the Ashikaga did, and therefore did not receive high positions in the Kamakura shogunate. This may have been one of the reasons why Yoshisada rose against the Hōjō clan in 1333.
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Natsume Yoshinobu

Yoshinobu, a long-time vassal of the Matsudaira and Tokugawa clans, governed Hamamatsu Castle on behalf of the Tokugawa house. During the clashes between the Imagawa, Takeda, and Matsudaira clans, he served in the garrison of Nagasawa Castle and in 1562 took part in raids under the command of Itakura Shigezane. When, in 1563, a revolt of the Sōtō-shū sect followers broke out in Mikawa Province, Yoshinobu joined the rebels together with Honda Masanobu and Hachiya Sadatsugu.
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Nambu Nobunao

The Nambu clan was an ancient and powerful family that traced its lineage back to the Minamoto shoguns and had controlled a significant part of the Tohoku region in northern Honshu since the 12th century. Nobunao was born in Ikatai Castle, located in what is now the city of Iwate. He was the second son of Ishikawa (Nambu) Takanobu, the 22nd head of the Nambu clan. In 1565, Nobunao’s uncle, Nambu Harumasa, adopted him, brought him to Sannohe Castle, and named him his heir, later giving his daughter in marriage to him.
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Naito Ienaga

Ienaga was the son of Naitō Kiyonaga and served Tokugawa Ieyasu from an early age. Like his father, he was exceptionally brave, and thanks to his remarkable skill with the bow, he earned the nickname “the unrivaled archer.” Although both the elder and the younger Naitō belonged to the Jōdo Shinshū (“True Pure Land”) sect, during the Ikkō-ikki uprising in Mikawa Province in 1565, Ienaga did not support his fellow believers and instead sided with Tokugawa Ieyasu, earning his special trust. He later took part in the battles of Mikatagahara, Nagashino, and many other engagements while accompanying Ieyasu.
