徳川秀忠
Oyumi Domain was created in February 1627, when Morikawa Shigetoshi, a "hatamoto" in the service of Shōgun Tokugawa Hidetada acquired holdings in Sagami, Kazusa and Shimōsa Provinces with revenues exceeding the 10,000 "koku" necessary to qualify as a "daimyō". He was allowed to build a "jin'ya" on the site of the Sengoku period Oyumi Castle. He later rose to the post of "rōjū", and committed "junshi" on the death of Tokugawa Hidetada. His successors continued to rule Oyumi Domain until the Meiji Restoration.