Originally there was only the Emonfu, but it was temporarily abolished in 808 due to its integration with Eshifu (whose functions were the same as those of Emonfu); then in 811, Emonfu was restored along with the renaming of Sayu Eshifu (left and right division of the outer palace gate guard), and.Saemonfu (left division of outer palace gate guard) and Uemonfu (right division of outer palace guard) were positioned there.
当初は1つであったが、大同_(日本)3年（808年）に（左右）衛士府と統合されて一旦廃止され、弘仁3年（811年）に左右衛士府の改称に伴って復置された際、左衛門府と右衛門府の２つが置かれた。