Actually there were a case in which 24 shogunal retainers of the eastern provinces (Togoku) inclulding MINAMOTO no Yoshitsune in the time of MINAMOTO no Yoritomo, were appointed directly and were forbidden to go east of Sunamoto (Gifu).
実際には、頼朝の時代に源義経をはじめ、24人の東国御家人が自由任官をし、墨俣以東に入ることを禁ぜられた事例がある。