The theoris on the origin of the ingubunkokusei system describes: One that it started when kanmotsu (tribute goods paid as taxes or tithes) and choyo (taxes in tribute and labor under the ritsuryo system) collected within Awaji Province were used to feed Imperial Prince Oi who had been deported to the province and called Awaji Haitei (deposed Emperor of Awaji); another theory argues that the system began when denso (a rice field tax) and rice collected within Yamato Province was used to feed Retired Emperor Heizei who had confined himself in Heijo-Kyo; a third theory states that the system was established along with shinno nintoku (provinces whose governing posts were reserved as sinecures for imperial princes) system that was introduced later on.
その由来については淡路国に流された淡路廃帝大炊親王（淳仁天皇）のために同国の官物・庸調が廃帝の生活に充てられ、平城京に籠った平城上皇のために大和国の田租・地子イネが生活に充てられたもの、更にその後導入された親王任国を制度の嚆矢とする説もある。