What is "jishukan"

Jishūkan was the Han school of Kumamoto, Japan existing between 1755 and 1870. It was established by Hosokawa Shigekata, the 6th Hosokawa clan daimyo of Higo Province, Kumamoto, Kumamoto, inside Kumamoto Castle and this school is known for producing many noted scholars such as Yokoi Shounan, Inoue Kowashi and Kitasato Shibasaburo.