Eusebius of Caesarea, also known as Eusebius Pamphilus, was a Greek Syro-Palestinian historian of Christianity, exegete, and Christian polemicist. In about AD 314 he became the bishop of Caesarea Maritima in the Roman province of Syria Palaestina. Together with Pamphilus, he was a scholar of the biblical canon and is regarded as one of the most learned Christians during late antiquity. 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. He also produced a biographical work on Constantine the Great, the first Christian Roman emperor, who was Augustus between AD 306 and AD 337.

Caesarea, also Caesarea Maritima, Caesarea Palaestinae or Caesarea Stratonis, was an ancient and medieval port city on the coast of the Eastern Mediterranean, and later a small fishing village. It was the capital of Roman Judaea, Syria Palaestina and Palaestina Prima, successively, for a period of c.650 years, and a major intellectual hub of the Mediterranean, from the time of Herod I until the Muslim conquest of the Levant. Today, the site is part of the Caesarea National Park, on the western edge of the Sharon plain in Israel.