AVELLANA, COLLECTION. — This is a collection, compiled by an unknown author in Rome in 553 or shortly thereafter, containing various documents from the years 367–553, especially papal letters (decretals) and imperial rescripts or constitutions, as well as a few other documents issued by lesser ecclesiastical or secular authorities. It is of great interest for ecclesiastical history and also, though to a lesser degree, for canon law, especially because the text of many—approximately 200—of the documents contained in it is not found in any other collections that have come down to us, nor is it otherwise known (it is probable that the compiler drew not only on sources and private collections now lost, but also directly on the papal archives); and furthermore because a large part of them constitutes valuable documentation concerning events of great historical importance: such, for example, as the exile of Pope Liberius, the schism of Ursinus, the question of Caelestius, and the question of the Three Chapters. Also noteworthy are groups of letters by the popes Simplicius, Gelasius I, and Hormisdas.
It is held that all the documents contained in this collection are authentic, with the exception of epistles nos. 71–78, which present themselves as addressed to Bishop Peter of Antioch.
The collection has been preserved for us in eleven codices: two parchment manuscripts from the eleventh century; the others paper manuscripts, from the fifteenth to the seventeenth centuries. The name A. was given to this collection by the Ballerini brothers, who believed that the most authoritative codex was the one found in the monastery of S. Croce di Fonte Avellana (diocese of Gubbio): a parchment codex, perhaps from the first half of the eleventh century (now cod. Vaticano 4661). This opinion remained undisputed for a long time, until Guglielmo Meyer, and more recently Otto Günther, demonstrated instead that the oldest and most authoritative is cod. Vat. lat. 3787, probably from the beginning of the eleventh century.
Many incomplete editions were produced, the first of them in Rome in 1591, under the direction of Cardinal Antonio D'Aquino (later completed by Baronio, in vols. IV–VII of his Amali); the only complete and critical edition is that of O. Günther, in vol. XXXV of the Corpus scriptorum ecclesiasticorum latinorum (Vienna 1895–98).