Mizuno Katsushige

Who They Were

Mizuno Katsushige (水野勝成, みずの かつなり) was a samurai and daimyo — a territorial lord — whose career stretched across one of the most violent and fluid stretches of Japanese history. He was born on 20 September 1564 in Okazaki, in Mikawa Province, the son of Mizuno Tadashige. His life ended on 4 May 1651, by which time the wars that defined his generation had been over for decades.

He is remembered as a fighter first. Katsushige took part in campaigns against the Takeda clan, the Tenshō-Jingo war, the Kyūshū campaign, the Battle of Komaki and Nagakute, the Battle of Sekigahara, the Siege of Osaka, and the Shimabara Rebellion. That list spans nearly fifty years of continuous warfare, from his youth in the 1570s to the Shimabara Rebellion of the late 1630s.

He was also, by the standards of his own time, unusually mobile in his loyalties. Katsushige changed allegiance repeatedly during his career before finally returning to the service of his original lord, Tokugawa Ieyasu. He then served the Tokugawa shogunate across three generations of shoguns, through to Tokugawa Iemitsu.

Life and Career

Katsushige was born in Eiroku 7, the seventh year of the Eiroku era, in Okazaki. His father was Mizuno Tadashige, and his mother was Myōjun-ni. The Mizuno were a Mikawa family, and Mikawa was the home province of the Tokugawa, which shaped the direction of his entire life.

His early military experience came against the Takeda clan, the great rival power of the Tokugawa in eastern Japan. He fought in the Tenshō-Jingo war, a conflict over the provinces of Kai, Shinano and Suruga, and in the Kyūshū campaign, the Tokugawa-aligned push into the southern island. He was present at the Battle of Komaki and Nagakute, and at the Battle of Sekigahara, the decisive engagement of 1600 that settled the national order for the next two and a half centuries.

He also fought at the Siege of Osaka, the two-part campaign that finally destroyed the Toyotomi house, and at the Shimabara Rebellion, the uprising of mostly Christian peasants on the Shimabara Peninsula. That last campaign belongs to a much later phase of his life, when he was already an established lord rather than a rising warrior.

Between these campaigns Katsushige spent periods as a rōnin — a masterless samurai — and served different patrons. The pattern was striking enough that contemporaries gave him a nickname: Rin kai fuki (倫魁不羈), which is glossed as meaning "too awesome to serve only one lord." In the end he returned to Tokugawa Ieyasu and stayed. He served the shogunate under Ieyasu, under the second shogun Tokugawa Hidetada, and under the third, Tokugawa Iemitsu.

He held the court title Koretō Hyūga no Kami (惟任日向守). The title of Hyūga no Kami had been avoided since Akechi Mitsuhide, who betrayed and killed Oda Nobunaga in 1582 and bore a lasting reputation as a traitor. Superstition attached to the title as a result. Katsushige took it anyway, indifferent to Mitsuhide's reputation, and earned the nickname Hyūga Demon (鬼日向) in consequence.

He married a woman known as Mimura O-san. Four sons are recorded: Mizuno Narikoto, Mizuno Katsutoshi, Mizuno Katsutada, and Mizuno Narisada. He died on 4 May 1651.

Why They Matter

Katsushige's career is a case study in how the Sengoku period actually worked. The popular image is of rigid loyalty to a single lord, but men of his rank frequently shifted patrons, fought for whoever offered the best position, and returned to old masters when circumstances changed. Katsushige did this more visibly than most, and the nickname he earned shows that his contemporaries noticed — and, importantly, did not destroy him for it. He ended his life as a daimyo in good standing under the third Tokugawa shogun.

His presence at Sekigahara and at the Siege of Osaka places him at both of the events that bookend the unification of Japan. His presence at Shimabara places him at one of the defining domestic crises of the early Edo period. Few careers touch so many of the era's turning points.

He was also a friend of Miyamoto Musashi, the most famous swordsman in Japanese history and himself a rōnin. That friendship, together with Katsushige's own wandering years, generated a body of anecdotes that circulated long after his death.

The Name in Japanese

The name is written 水野勝成. It is read みずの かつなり in kana, and rendered in romaji as Mizuno Katsunari — the reading recorded for him is かつなり, though the final kanji 成 is also commonly read shige, which is why he appears in some sources as Katsushige.

Breaking it down character by character:

水 — read mizu. Meaning: water. It is a pictograph of flowing water, and it is one of the most common elements in Japanese surnames.

野 — read no. Meaning: field, plain, open country. Combined with 水, the surname 水野 (Mizuno) literally suggests "water field" — a wet plain or marshy open ground. This is the family name, placed first, as is standard in Japanese.

勝 — read katsu. Meaning: victory, to win, to excel. It appears in many samurai names of this period, and it is the character that carries the martial sense of the given name.

成 — read nari here. Meaning: to become, to accomplish, to complete. Paired with 勝, the given name 勝成 carries the sense of "victory achieved" or "one who wins and completes."

The full name in Japanese order is surname first: 水野 (family) + 勝成 (given name). The alternative form 勝成 read as Katsushige uses the same two characters; only the reading of the second differs. The kana reading みずの かつなり is the one to use when saying the name aloud.

Legacy

Katsushige's memory survived in two forms. The first is the record of his campaigns: Takeda, Tenshō-Jingo, Kyūshū, Komaki and Nagakute, Sekigahara, Osaka, Shimabara. The second is the body of stories that grew around his wandering years, his repeated changes of allegiance, and his friendship with Miyamoto Musashi.

The nickname Rin kai fuki (倫魁不羈) outlived him as a byword for a warrior too independent to belong to any single master. The nickname Hyūga Demon (鬼日向), earned by his willingness to take a title others feared, attached to him for the same reason — a reputation for refusing to be constrained by other people's superstitions.

He died on 4 May 1651, having served the Tokugawa shogunate through three successive shoguns. His sons carried the Mizuno name forward.