Furthermore, in the middle ages, the establishment of Myoden (rice field lots with a nominal holder) and the introduction of "ronin" accompanying environmental improvement by kokuga (provincial government offices) and shoen landholders led to active development of Koden.
更に中世に入ると、名田の成立や国衙や荘園領主による環境整備を伴った「浪人」導入よって荒田に対する積極的な開墾が見られるようになる。