GIOVANNI DIACONO, called HYMONIDES. – Born c. 1825, died before 1882. A monk of Monte Cassino, friend of Anastasius the Librarian, he exercised great influence at the court of Pope John VIII (872-82). Commissioned by the Pope to write the life of St Gregory the Great, he composed the fullest biography of the great Roman Pontiff, which remains the best of the ancient lives, written with historical good sense, in thematic form, according to the four books of the Regula pastoralis, rather than chronologically.
His literary authorship of other works is not fully established. According to Latin sources he began, at the request of Gualerico of Velletri, a life of St Clement of Rome, and turned the apocryphal Convivium (Symposion), commonly called the Caena Cypriani (v. Cipriano), into 375 verses. His collaboration on the Liber Pontificalis is probable.