Catholic Church. Cancellaria Apostolica

The origin of this office goes back to the fourth century when notaries were appointed to draw up papal documents. These notaries of the Roman church were headed by the primicerius, who was in turn aided by a secundicerius. The notaries, in their capacity as scriniarii, also supervised the archives. Up until the eighth century documentation concerning this office is limited.

Gregory the Great, following the example of the Roman emperors of the East, gathered the notarii of the church into a school (schola notariorum) presided over by the primicerius notariorum and assisted by the secundicerius (letter of March 598). The primicerius, in his office as head of the palatine judges (iudices palatini), was the most influential official in the papal administration. By the end of the eighth century the duties of primicerius had been united to those of the bibliothecarius (librarian) and the latter title was used for nearly a century.

...