The Naito clan (内藤氏)

Naito-shi or Naito-uji is a Japanese surname. The Naito clan is a clan of gozoku (local rulers) and daimyo (feudal lords) which has flourished from the Middle ages to Modern times.

The Naito clan of the Northern House of the Fujiwara clan, Hidesato Line (Michinaga Line)

The following Naito clans are well known. Moriie NAITO and Moritoki NAITO who served MINAMOTO no Yoritomo in the Kamakura period were the common ancestors of those Naito clans mentioned below.

Shugodai (the acting Military Governor) of Tanba Province
This Naito clan served the Hosokawa clan. It claimed to be the Fujiwara clan, Hidesato line.

Shugodai (the acting Military Governor) of Nagato Province
This Naito clan served the Ouchi clan. It claimed to be the Fujiwara clan, Hidesato line or Michinaga line.

The gozoku (local ruling family) of the Province of Mikawa, serving the Matsudaira family
It claimed to be descended from the same family as the first two Naito clans mentioned above.

A family of Kai Province
This Naito clan is thought to share the common ancestors of the first two Naito clans mentioned above. It served the Takeda clan. Masatoyo NAITO was a prominent figure.

The Naito clan of Tanba lineage

This Naito clan is thought to be descended from the family of Fujiwara no Hidesato-Fujiwara clan, but its background is not well known. However, since it was called Hosokawa-Uchishu (the Hosokawa houseman), it may have provided immediate retainers to the Hosokawa clan.
When Motosuke KOZAI, the shugodai of Tanba, was dismissed in 1431, Nobusuke NAITO, a direct vassal of the Hosokawa clan, became the shugodai, and the Naito clan then set up a base in the Funai district Yagi and began to rule Tanba
However, because the Hosokawa clan used the Shugo system, a county-by-county ruling system, as the governing system for its territory, it is uncertain whether the Naito clan ruled the whole of Tanba. In the Onin War, the Naito clan, accompanied by other local ruling families of Tanba, fought at Yakuno with the generals of the Otagaki clan which had supported the Yamana clan from Tajima Province.

However, Motosada NAITO was relieved of the shugodai post in 1482 due to some sort of trouble with the Ichinomiya clan, the Hosokawa clans's direct vassal, in 1479. Motosada was replaced with Motohide UEHARA from a local ruling family from Tanba Mononobe. Motohide was greatly trusted by Masamoto HOSOKAWA, but he behaved so arrogantly that other local ruling families of Tanba became resentful, and this led to the Iden Uprising in September 1489. As a consequence, Motohide UEHARA was dismissed in 1495, and Motosada NAITO was reinstated as shugodai.

Thereafter, the Hosokawa clan split into two groups, one led by Takakuni HOSOKAWA and the other by Harumoto HOSOKAWA, with the result that the Naito clan and other local ruling families of Tanba, which belonged to the Takakuni group, were frequently attacked by the Harumoto group. The position of the Naito clan at the entrance to Tanba meant that they, more often than the other families, suffered direct attacks from the Hosokawa clan. There is a view that these dramatic and repeated replacements of the shugodai show how deeply the Naito clan was involved in the internal conflict of the Hosokawa clan.

The power of the Naito clan waned as the Hatano clan, which built Yakami-jo Castle in 1515 as its base, gradually expanded its power. The Hatano clan defeated Kunisada NAITO, and captured Tanba in 1533, but Hidetada HATANO, allied with the Miyoshi clan, brought about the surrender of Yakami-jo Castle in 1538. Therafter, Kunisada also allied himself with Nagayoshi MIYOSHI and resisted the Hatano clan with the help of the Yakami-jo Castle, but was killed in battle in September 1553, bringing about the downfall of the Naito clan as Warring loads.

Nagayoshi MIYOSHI took over Yakami-jo Castle in 1553 and arranged a marriage between Nagayori MATSUNAGA and the Naito clan, whereupon Nagayori became lord of the castle and pursued the conquest of Tanba, but Nagoyori was really no more than a puppet of the Miyoshi administration, and, after the death of Nagayoshi, was killed in a fierce attack by Naomasa AKAI in August 1565.

Sadakatsu NAITO, a son of the late Kunisada NAITO, went to Kyoto to fight with Nobunaga ODA for the decisive battle between Nobunaga and Yoshiaki ASHIKAGA in 1573,
Sadakatsu is also thought to be the member of the Naito clan who later joined the conquest of Tanba by Mitushide AKECHI.
It was Sadakatsu who professed Christianity, and was later to become Joan NAITO. (Joan is also said to be a son of Munekatsu NAITO.)
He served Hideyoshi TOYOTOMI, was a member of the expeditionary force to Korea, and was involved in peace negotiations with Yukinaga KONISHI. He later served in the Kaga domain, but when the ban on Christianity was imposed in 1614, he was exiled to Manila where he remained until his death in 1626.

The Naito clan of Suo Nagato lineage

This Naito clan was related to the Hidesato-Fujiwara of the Fujiwara clan (or Fujiwara no Michinaga). It settled in Suo Province. The generation of Morisada NAITO served the Ouchi family, but from the mid-Muromachi period onwards, members of the clan were appointed as shugodai of Nagato province in place of the Washizu family. Hironori NAITO who served Masahiro OUCHI, and Okimori NAITO who served Yoshioki OUCHI and Yoshitaka OUCHI were prominent figures. Takayo NAITO, a grandson of Okimori, committed seppuku at the downfall of the Ouchi clan, ending the main line of the family, but Takaharu NAITO, Okimori's fifth son, served the Mori clan. He was entrusted with an important position because Terumoto MOURI's mother came from the Naito clan, but when his adopted son, Motomori NAITO, made a triumphal entry into the Osaka-jo Castle in the Siege of Osaka, he was forced to commit seppuku with his son, Motoyoshi NAITO, and the fortunes of the family declined. The family line continued as vassals of the Choshu domain.

The family tree: the head of the family is indicated in bold letters, biological children with heavy lines, and adopted children with thin or double lines

The Naito clan of Mikawa lineage

This Naito clan, which was a vassal to the Matsudaira clan (the Tokugawa clan) in Mikawa Province and provided daimyo (feudal lords) during the Edo period, is documented to share ancestors with the Naito clans of Tanba and Suo mentioned above, but the history of the clan during the Sengoku period (the Warring States period) is not known, and there is strong possibility that the pedigree was fabricated. From the Sengoku period (Japan's Warring States period) to the Azuchi-Momoyama period, Kiyonaga NAITO, Masashige NAITO, Ienaga NAITO, and Nobunari NAITO served Ieyasu TOKUGAWA, and worked so hard that the family was granted the right to establish several branch families, which flourished and provided hereditary daimyo to the Tokugawa House.

The family tree: the head of the family is indicated in bold letters, biological children with heavy lines, and adopted children with thin or double lines

The Naito clan of Kai lineage

Some of the Naito Clan settled in Kai. It served the Takeda clan for generations, but was discontinued temporarily when Toramoto NAITO was killed by Nobutora TAKEDA.

Masatoyo NAITO (Sukenaga KUDO), who was one of the Twenty-Four Generals of the Takeda clan, was born into the Kudo clan, his father, Toratoyo KUDO serving the Takeda clan in Kai. Although Toratoyo temporarily allied himself with the Oyamada clan and Nobushige ABURAKAWA, who fought against and lost to Nobutora TAKEDA, he was allowed to return to the Takeda family's service. Nobutora subsequently froze out Toratoyo and put him to death together with Toramoto, causing the Kudo clan family, including Sukenaga, Toratoyo's son, to flee Kai Province. Shingen TAKEDA later exiled Nobutora and called back Sukenaga, a son of the late Toratoyo, who regained the domain for the Kudo clan. Sukenaga worked so earnestly for Shingen that he was allowed to use the name of the Naito clan, the distinguished family in Kai, which had been discontinued since Toramoto's death, and subsequently changed his name to "Masatoyo NAITO."

After Shingen's death, Masatoyo was killed in the Battle of Nagashino. Thereafter, Masaaki NAITO, an adopted child from the Hoshina clan, carried on the family name while serving Hoshina family in Aizu (later known as the Matsudaira clan in Aizu).

The other Naito clans

A family (the Sagami-Naito clan) which claimed to be of Naito clan and also identified itself as the Hidesato group existed in Sagami Province, but the origin of this family is uncertain. There was also a person called Katsusuke NAITO who served Nobunaga ODA, but his origin is unknown. The direct vassals of the Takeda clan in Wakasa Province also included a Naito clan family.