In the fifth century he appears as head of the college of priests, as the bishop's delegate for certain duties of visitation and canonical judgment, as his representative in case of absence or death (sede vacante).
He is promoted by presentation to the patriarch, who lays his hand on him with prayer, and the clergy cry "axios" (ἄξιος) three times (the rite from Allatius is given by Goar, 238).
He could ordain lectors; at concelebrations where no bishop is present he presided and said the ekphonesis (ἐκφώνησις - exclamations chanted aloud at the end of prayers and litanies).
George Kodinos (fourteenth century) says of the protopope: "he is first in the tribunal [τοῦ βήματος - tou bematos, in authority] holding the second place after the pontiff" (De Officiis, I, quoted by Goar 237).
So Theodore Balsamon (twelfth century): "It is forbidden by the canons that there should be bishops in small towns and villages, and because of this they ordain for these priests who are protopopes and chorepiscopi" (Syntagma, III, 142).