Eusebius of Caesarea (c. AD 263 – 339) also called Eusebius Pamphili, was a Roman historian, exegete and Christian polemicist. He became the Bishop of Caesarea in Palestine about the year 314. Together with Pamphilus, he was a scholar of the Biblical canon. He wrote Demonstrations of the Gospel, Preparations for the Gospel, and On Discrepancies between the Gospels, studies of the Biblical text. As "Father of Church History" he produced the Ecclesiastical History, On the Life of Pamphilus, the Chronicle and On the Martyrs

Eusebius' Life of Constantine is the most important single record of Constantine, the emperor who turned the Roman Empire from prosecuting the Church to supporting it, with huge and lasting consequences for Europe and Christianity. The only English version previously available is based on a seventeenth-century Greek edition, but two new critical editions produced this century make a new English version necessary. The authors of this edition present the results of the recent scholarly debate, as well as their own researches so as to clarify the significance of Eusebius' work and introduce the student to the text and its interpretation, thus opening up the contentious issues. At face value much of what Eusebius wrote is false. This book shows how, once his partisan interpretations and rhetoric are properly understood, both Eusebius' text and the documents it contains give vital historical insights.