AUGUSTINE of Aquileia 408 434. Successor to St. Chromatius as bishop of Aquileia. His activity is known to us only because of the Pelagian heresy. He seems in fact to have been the recipient of a Libellus fidei of a group of northern Italian bishops and clergy, protesting against certain measures that Augustine, the metropolitan of Aquileia, took in deference to orders of the court of Ravenna and to the document Tractoria, 418 in which Pope Zosimus denounced the Pelagian heresy and clearly set forth Catholic doctrine. There are doubts about who the Libellus fidei is addressed to, but it is very probable that, just as the Pelagians of southern Italy turned to Rufus of Thessalonica, those of the north tried to win over the metropolitan of Aquileia. G. Cuscito, Cristianesimo antico ad Aquileia e in Istria, Trieste 1977, 193-194 with bibl.; PCBE 2,223.