PETER THE DEACON OF MONTE CASSINO

Librarian and forger; b. Rome, probably 1107; d. after 1153. Peter went as a boy to monte cassino. He was a deacon by 1128 when Abbot Seniorectus exiled him as a sympathizer of the deposed Abbot Oderisius II. After his recall in 1130, he became bibliothecarius and supervised the compilation of the chartulary of the monastery, the Registrum Petri Diaconi. In 1137 he defended Monte Cassino's stand during the schism before the German Emperor lothair iii at Lago Pesole (see pierleoni).

Peter is known only from his own numerous writings, many of which survive in the autograph codices Casinenses 361 and 257. Both MSS contain his autobiography. His handwriting is therefore known; it is"an uneven ordinary minuscule" (Willard), not the Beneventan calligraphy used in the Registrum Petri Diaconi and the Registrum s. Placidi, a corpus of hagiographical works pertaining mainly to St. Placidus, composed by him. Hence, as Meyvaert proved, Peter "wrote" neither these MSS nor the marginalia of MS Munich Clm 4623 of leo marsicanus of Ostia's Chronicle of Monte Cassino and of codex Casinensis 413 (Translatio s. Mennatis ).

Many of Peter's writings are careless excerpts from the works of others (e.g., the exegetical treatises in codex Casinensis 257) or outright forgeries. He may be one of the most prolific and brazen forgers in history, and studies in progress will show him to have been a pathological case. Some of these forgeries center around saints such as Placidus or maurus, St. Benedict's pupils, or Mark of Atina, an alleged disciple of St. Peter, and are buttressed by works of his invention ascribed to earlier authorities. The Atina papers, believed to be lost, were rediscovered in 1951 and will be edited by H. Bloch. Peter's historical works include the Liber illustrium virorum archisterii Casinensis and the Ortus et vita iustorum cenobii Casinensis, dictionaries of Monte Cassino's outstanding men and saints. His exact contribution to the Chronica mon. Casinensis, started by Leo of Ostia, continued by his own teacher Guido, and brought up to 1138 by Peter himself, remains to be determined.

Bibliography: e. caspar, Petrus Diaconus und die Monte Cassineser Fälschungen (Berlin 1909), fundamental. h. bloch, "The Schism of Anacletus II and the Glanfeuil Forgeries of P. the D.," Traditio 8 (1952) 159–264. p. meyvaert "The Autographs of P. the D.," The Bulletin of the John Rylands Library 38 (1955) 114–138; "The Exegetical Treatises of P. the D.," Sacris Erudiri 14 (1963) 130–148. p. meyvaert and p. devos, "Autour de Léon d'Ostie et de sa Translatio S. Clementis, " Analecta Bollandiana 74 (1956) 211–223, with ref. to the earlier articles by W. Smidt and H. W. Klewitz on the Chronica Casin. a. mancone, "Il Registrum P. D," Bullettino dell'Archivio paleografico Italiano 2–3 (1956–57) pt. 2:99–126. h. wolter, Lexikon für Theologie und Kirche, ed. j. hofer and k. rahner (Freiberg 1957–65) 8:360–361.

[h. bloch]