The idea of jejo was firstly used in
Song and
Yuan dynasty, which arrived in the late Goryeo period. Although Song and Won took the seat as normal affair of government, Goryeo adopted the status largely for unsteady or irregular seats. Therefore, "pujejo" could mean someone in
emeritus or temporary worker. Later in Joseon, the number of jejo officer highly increased as concurrent seats, making out of dojejo and pujejo. Before Gyeongguk daejun was written, there had been dojejo, jejo and Pujejo; each possessed specific hierarchy of government. According to Gyeongguk daejeon, the number of officers can be found; five for Saongwon, one each for
Naeuiwon,
Sanguiwon and Jeonokseo, while Seungmunwon did not designate exact number. ==See also==