Starting around the middle of the 13th century, the social system started changing drastically: For example, money had become used in the economy, goods were circulated actively, and samurai, such as jito (managers and lords of manors), had advanced into shoen koryo (public lands and private estates).
13世紀中期頃から、貨幣経済の浸透と商品流通の活発化、村落の形成、地頭ら武士による荘園公領への侵出など、大きな社会変動が生じ始めた。