Ōsumi Province
Sometime around 1140, the whole island of Tanegashima became part of the Shimazu Estate, the largest medieval "shōen" of Japan. In the early Kamakura period, the positions of the land steward of the Shimazu Estate and the military governor of Ōsumi Province were given to the Shimazu clan. However, the clan lost these positions to the Hōjō clan, the de facto ruler of the shogunate. The Hōjō clan sent the Higo clan as deputy governors. A branch line of the Higo clan made itself autonomous on Tanegashima after the Hōjō clan was annihilated and began to claim the clan name of Tanegashima.