Kai Province was initially entrusted to important Tokugawa clan members as Kōfu Domain, and later to the highly placed fudai daimyō Yanagisawa clan, with periods of direct shogunal rule ( tenryō ) in between. Following the transfer of Yanagisawa Yoshisato to Yamato Province in 1724, the domain remained under direct shogunal control until the Meiji Restoration.
With the abolition of the han system in July 1871, Kōfu Domain became “Kōfu Prefecture”, which subsequently was renamed Yamanashi Prefecture.
List of daimyōEdit
# Name Tenure Courtesy title Court Rank kokudaka Notes Tokugawa clan, 1603-1704 (shinpan)  1 Tokugawa Yoshinao (徳川義直) 1603–1607 Uhōe-no-kami (右兵衛督) Lower 4th (従四位下) 250,000 koku 9th son of Tokugawa Ieyasu 2 Tokugawa Tadanaga (徳川忠長) 1618–1624 Gon-Chūnagon (権中納言) Third (従三位) 238,000 koku 3rd son of Tokugawa Hidetada 3 Tokugawa Tsunashige (徳川綱重) 1661–1678 Sangi (参議) 3rd (従三位) 250,000->350,000 koku 3rd son of Tokugawa Iemitsu 4 Tokugawa Tsunatoyo (徳川綱豊) 1678–1704 Gon-Chūnagon (権中納言) 3rd (従三位) 350,000 koku 1st son of Tokugawa Tsunashige
became 6th Shōgun, Tokugawa Ienobu
Yanagisawa clan, 1704-1724 (fudai) 1 Yanagisawa Yoshiyasu (柳沢吉保) 1704–1709 Mino-no-kami (美濃守); Sakonoe-shoshō (左権少将) Lower 4th (従四位下) 150,000 koku transfer from Kawagoe Domain 2 Yanagisawa Yoshisato (柳沢吉里) 1709–1724 Kai-no-kami(甲斐守)
3rd (従三位) 150,000 koku Eldest son of Yanagisawa Yoshiyasu
transferred to Yamato-Kōriyama Domain
Tokugawa clan, 1724-1871(tenryō) 
- Papinot, E (1910). Historical and Geographic Dictionary of Japan. Tuttle (reprint) 1972.
- "Kōfu" at Edo 300 (in Japanese)