In addition, according to a view, the starting point of the rice field tax of the ritsuryo system was the first crop of the season offered to the head of a province (powerful local clan) for doing a shrine ritual; the Imperial court which was based on the ritsuryo system took away the political and religious power from the powerful local clan and ordered the first crop of the season to be offered to the court and it is said that the system of fudokoku was to separate the rice field tax from the heads of local provinces.
なお、一説によれば、律令制における田租の原点は、神事の遂行のために在地首長（豪族）へ献上されていた初穂であったとされ、在地首長から政治的・宗教的権限を剥奪した朝廷（律令政府）がその初穂を自己に納めさせたものであり、不動穀化はそれを囲い込むことによって在地首長と田租を切り離す目的があったとも言われている。