Ōkubo Tadasuke

Who They Were

Ōkubo Tadasuke (大久保忠佐) was a samurai commander who fought through the bloodiest decades of Japan's unification wars and lived to become a feudal lord. Born in 1537, he served Tokugawa Ieyasu, the warlord who would eventually found a dynasty of shoguns, and he was present at many of the campaigns that built Tokugawa power. By the end of his life he held Numazu Domain in Suruga Province, assessed at 20,000 koku — a koku (石) being the traditional unit of rice sufficient to feed one person for a year, and the standard measure of a lord's wealth and standing.

He belonged to the Ōkubo family, a warrior house whose fortunes rose alongside the Tokugawa. His father was Ōkubo Tadakazu, and his mother was a daughter of Sanjōnishi Kineda. Tadasuke's career began in the Muromachi period (1336–1573), the long era of shogunal rule in Kyoto that was collapsing into civil war, and ended in the early Edo period, when the Tokugawa had imposed peace on the country. He died on 9 November 1613.

Life and Career

Tadasuke was born in 1537, in the sixth year of the Tenbun era (天文), a period when Japan had no effective central government and regional warlords fought constantly for territory. He grew up in the service of the Tokugawa house, then based in the Mikawa region, and spent his adult life in the field.

In 1572 he fought at the battle of Hitokotosaka alongside Honda Tadakatsu, one of Ieyasu's most celebrated generals, against forces of the Takeda clan. The Takeda, led by Takeda Shingen and later his son Katsuyori, were the Tokugawa's most dangerous rivals, and the fighting between them shaped Tadasuke's generation of warriors.

He went on to take part in the campaigns that destroyed the Takeda clan, in the battle of Komaki and Nagakute, and in the decisive battle of Sekigahara. Sekigahara, fought in 1600, was the engagement that broke the last great coalition against Ieyasu and made Tokugawa supremacy unavoidable. Tadasuke's presence there places him among the commanders who won the Tokugawa century.

His reward was lordship. He received Numazu in Suruga Province, a domain assessed at 20,000 koku, and governed it as daimyō. The title daimyō (大名) means "great name" — a lord who held enough land to maintain a substantial military household and who answered, in this era, to the Tokugawa regime.

Tadasuke died on 9 November 1613, in the eighteenth year of the Keichō era, without an heir. Because no successor had been designated, his 20,000 koku at Numazu was confiscated and the domain reverted to the Tokugawa shogunate.

Why They Matter

Tadasuke's importance lies in what he represents: the generation of provincial warriors who fought for Ieyasu from the 1550s through 1600 and were rewarded with domains when the wars ended. The Tokugawa order that governed Japan for more than two and a half centuries rested on men like him — commanders who had survived the unification campaigns and now became the landed aristocracy of the peace.

His career also illustrates how fragile a daimyō house could be. A lifetime of service and a domain of 20,000 koku counted for nothing without an heir. When Tadasuke died in 1613, the shogunate absorbed Numazu rather than allow the line to continue, a reminder that under the Tokugawa, inheritance rules and family continuity mattered as much as battlefield record.

There is also the matter of his survival. It was recorded that despite participating in many battles, Tadasuke never received a single wound during his career. Jōzan Yuasa, a samurai retainer of the Okayama clan and a Confucian scholar who collected anecdotes during the Edo period, recorded that Tadasuke once boasted he had received only thirteen wounds in battle during his lifetime as a soldier. The two accounts sit oddly together, but both point to the same thing: a long military career in an age of extreme violence, and a reputation for coming through it.

The Name in Japanese

The name is written 大久保忠佐. It is read in kana as おおくぼ ただすけ, and in romaji as Ōkubo Tadasuke. The family name comes first, as is standard in Japanese.

The surname 大久保 breaks into three characters:

• 大 — read ō here. It means "great" or "large."
• 久 — read ku here. It means "long-lasting" or "of long duration."
• 保 — read bo here. It means "to protect," "to keep," or "to preserve."

Together the surname suggests something like "the great, long-preserved place" — a name with connotations of endurance and safekeeping, fitting for a warrior house.

The given name 忠佐 breaks into two characters:

• 忠 — read tada here. It means "loyalty" or "devotion," a virtue prized above almost all others in samurai culture and extremely common in warrior names of this period.
• 佐 — read suke here. It means "to assist" or "to help," and appears frequently as the second element in male given names of the era, often indicating a supporting or auxiliary role.

So the given name carries the sense of "loyal assistance" — a name that announces the ideal of a retainer who serves faithfully. Note that the same kanji can be read differently depending on the name: 忠 appears as tada in Tadasuke but as chū in many other words, and 佐 appears as suke in names but as sa elsewhere. Japanese personal names are chosen for their sound and meaning together, and the readings are not predictable from the characters alone.

Legacy

Tadasuke's direct line ended with him. He left a daughter, who married Aoyama Tadatoshi, and a son named Ōkubo Tadakane, but no heir was recognised to inherit Numazu, and the domain passed back to the Tokugawa shogunate in 1613.

What survives of him is the record of his service: a participant in the destruction of the Takeda, at Komaki and Nagakute, and at Sekigahara, and a lord of Numazu for the final years of his life. The anecdote preserved by Jōzan Yuasa — the boast of thirteen wounds, or the claim that he took none at all — is the kind of story Edo-period scholars liked to collect about the old warriors, and it is the image of Tadasuke that endured: a soldier of the unification wars who came through them.