Mizuno Tadakiyo was the eldest son of
Mizuno Tadakuni, the
daimyō of
Hamamatsu Domain and chief senior councilor (
Rōjū) in service to the
Tokugawa shogunate. After the failure of the
Tenpō Reforms, Tadakuni was forced into retirement and exile, and turned the leadership of the
Mizuno clan and the position of
daimyō of Hamamatsu Domain to Tadakiyo in 1845. However, the same year, Tadakuni was reassigned to
Yamagata Domain (50,000
koku) in
Dewa Province. After the pardon of his father in 1851, Tadakuni’s fortunes improved. Within the shogunal administration, he received the post of
Jisha-bugyō (Commissioner of Shrine and Temples) and
wakadoshiyori (Junior Councilor). In 1862, he became a
Rōjū in the service of
Shōgun Tokugawa Iemochi. As
Rōjū, he worked with
Oguri Tadamasa in the construction of
Yokosuka Naval Arsenal as part of the Tokugawa shogunate’s efforts to modernize Japan’s military. He retired from public life in 1866 on the death of
Shōgun Tokugawa Iemochi, and was succeeded at Yamagata by his son
Mizuno Tadahiro. Mizuno Tadakiyo was married to a daughter of
Inoue Masahari, a fellow
Rōjū and
daimyō of
Tanagura Domain. == References ==