Eusebius of Caesarea 260-339
Constantini imperatoris oratio ad sanctorum coetum
The Oration of the Emperor Constantine

Bibliographic Reference

A select library of the Nicene and Post-Nicene Fathers of the Christian Church. Second Series. Translated into English with prolegomena and explanatory notes. Volumes I-VII. Under the editorial supervision of Philip Schaff, D.D., LL.D., Professor of Church History in the Union Theological Seminary, New York and Henry Wace, D.D., Principal of King's College, London. Volume I: Eusebius Pamphilus: Church History, Life of Constantine, Oration in Praise of Constantine T&T Clark, Edinburgh, 1890. (Translation, English)