The
fudai Sakai clan originated in 14th century
Mikawa Province. The senior branch was founded by
Sakai Tadatsugu (1527–1596). Tadatsugu, a vassal of
Tokugawa Ieyasu, was charged with the defense of
Yoshida Castle in Mikawa Province. In 1578, Sakai Ietsugu (1564–1619) succeeded to his father's role as defender of Yoshida Castle. The
Ie- in the beginning of
Ietsugu's name was a special honor bestowed by Tokugawa Ieyasu, who intended to emphasize bonds of loyalty with those who were allowed to share in any part of his name. When Ieyasu's holdings were transferred to the Kantō region in 1590, Ietsugu was installed at Usui Domain (30,000
koku) in Kōzuke Province, but, in 1604, he was moved to
Takasaki Domain (50,000
koku). In 1616, he was again moved to
Takada Domain (100,000
koku), this time in
Echigo Province. In 1619, he was moved to
Matsushiro Domain in
Shinano Province; and then, from 1622 to 1868, he was installed at
Tsuruoka Domain (120,000
koku) in
Dewa Province. The Sakai of Tsuruoka (which later grew to 170,000
koku) in Dewa Province were prominent in the late Edo period as a military power. Charged with the safety of
Edo, they were patrons of the Shinsengumi police force, and were very effective in their duties. Following the surrender of Edo, the Sakai withdrew and returned north to their domain, where they were active in the northern theater of the
Boshin War, as well as becoming signatories to the pact that created the
Ōuetsu Reppan Dōmei in 1868. The head of this clan line was ennobled as a "Count" in the Meiji period. A cadet branch was created in 1647. In 1749, the descendants of
Sakai Tadakiyo (1626–1681) were transferred to
Himeji Domain (150,000
koku) in
Harima Province; and they remained daimyō at Himeji until the
Meiji period. These Sakai were installed from 1668 through 1868 at
Katsuyama Domain (12,000
koku) in
Awa Province. The head of this clan line was ennobled as a "Viscount" in the Meiji period. A further cadet branch of the Sakai had been created in 1681, These Sakai were installed in 1681 through 1868 at Isezaki Domain (20,000
koku) in Kōzuke Province. The head of this clan line was ennobled as a "Viscount" in the Meiji period.
Sakai Tadatoshi (1562–1627) received the fief of
Tanaka Domain (10,000
koku) in
Suruga Province in 1601; then his holding was transferred in 1609 to
Kawagoe Domain (30,000
koku) in Musashi province.
Sakai Tadakatsu (1587–1662) was installed in 1634 through 1868 at
Obama Domain (103,500
koku) in
Wakasa Province . This cadet branch of the Sakai had been created in 1590. The head of this clan line was ennobled as a "Count" in the Meiji period. Finally, another cadet branch of the Sakai had been created in 1682. These Sakai were installed in 1682 through 1868 at
Tsuruga Domain (10,000
koku) in Echizen Province. The head of this clan line was ennobled as a "Viscount" in the Meiji period. ==Family heads==