Eusebius of Caesarea

Eusebius was bishop of Caesarea Maritima and the most learned Christian of his generation, heir to the library built up there by Origen and Pamphilus. He lived through the Great Persecution under Diocletian and became an adviser and admirer of Constantine.

His Church History, completed around 325, is the first narrative history of Christianity. Its chief value lies in the sources it quotes, many otherwise lost: Papias, Hegesippus, Irenaeus’ letters, Hadrian’s rescript and the Testimonium Flavianum, of which he is the earliest witness. He also wrote a Chronicle and a Life of Constantine.