The Emergence of Papal Decretals: The Evidence of Zosimus of Rome

There are fewer than two dozen surviving letters of Zosimus, bishop of Rome from 417 to 418, preserved in a variety of places. The largest group is found in the Collectio Arelatensis, and concerns Zosimus’ response to the bishop of Arles who was claiming an expanded authority over several other Gallic metropolitan bishops. ¹ Others, mainly dealing with Zosimus’ response to Pelagianism, are found in the Collectio Avellana, that sixth-century collection of imperial and papal letters mostly not preserved elsewhere. ² A couple are found in a variety of manuscript collections in which they have been labelled as decretals rather than simply as letters. Since the earliest labelled document as a decretal is held to be a letter from Siricius (384–99) from the previous generation it could be concluded that we have evidence of a new literary genre appearing.