Mizuno was an official in the Tokugawa shogunate. He was a junior counselor (wakadoshiyori) in the 1770s.[1] From 3 November 1871 to 3 May 1788, he was a senior counselor (rōjū) at the top of the shōgun's hierarchy.[2]
In the political struggles of his time, he was a member of the faction headed by Tanuma Okitsugu.[3] He managed to survive Tanuma's downfall; and he worked for a time with Matsudaira Sadanobu.[4]
