Agnellus' Liber pontificalis ecclesiae Ravennatis (Book of Pontiffs of the Church of Ravenna) , written in the ninth century, is an essential source for the study of Italian history from the fourth to the ninth centuries. Agnellus seems to have been a well-born priest in the church of Ravenna, and his work is strongly colored by his personal experiences. He wrote the book to demonstrate two strongly-held opinions. One was the apostolicity and independence...