The earliest extant Greek commentary on the Apocalypse was written by a certain Ecumenius. Many questions surround the provenance of this commentary. Was it written early in the sixth century or does it rather stem from the later decades of that same century? Was it written by a Monophysite? or by a Chalcedonian? Was the author of this commentary a friend and ally of Severus of Antioch? If not, who then was he? Such questions are important because Ecumenius' commentary is important. It offers an early uncial text of the Apocalypse of great moment for the New Testament textual critic. It is a significant source for understanding late antique efforts to support the canonical authority of the Apocalypse.' It contains crucial evidence of developing Mariological doctrines. Even more interesting, however, is the commentary's place in the history of polemic against Origen. Such themes are subtle, yet so frequent that one could read the text primarily as an attempt to provide an eschatological vision orthodox enough to replace that of Origen and his followers. But these are matters for another time.2 Here our concern is that of establishing the provenance of this text-who wrote it? when? and where?