Sendai domain samurai, Confucianist and scholar of Chinese studies. Would become the head of Yokendo domain school in Sendai starting in 1865. From the 1840s, he also studied Western gunnery, becoming the head Western gunnery practitioner for the domain. His father, Gentaku, was a Dutch specialist, and in the 1850s Bankei promoted opening the country to trade with Russia, a country unsullied by the Opium Wars, as were Great Britain and the USA. His opinion was in the minority. During the Meiji restoration, Bankei fought hard on the side of the shogunate, and was imprisoned afterwards as a result. He was finally released in 1871, his life sentence commuted. During his life he had published four major books: "Sacrifice" about his theory of opening the country; "Yoneri Kanji and "Rousai Kanji" documenting his observations of the arrival of Perry and the Black Ships; "Kinko shidan" about the Sendai daimyo, which became high school required reading, and "The Mencius Treaty" about the Chinese philosopher.