EUSEBIUS OF CAESAREA (b. around 260 or shortly thereafter; d. 30 May 339 [or, less probably, 340]), Greek ecclesiastical historian and theologian. His parentage and exact place of birth are unknown; since no contemporary biography is extant, we are largely dependent on the evidence of his own writings for information on his life. Eusebius was imprisoned in 309 during the Diocletian persecution of Christians (303-313), after the end of which he became bishop of Caesarea in Palestine. At the Council of Nicaea (325) he played a prominent role at the right hand of the Emperor Constantine the Great, whose chief theological adviser he appears to have been; at the Council of Antioch (331) he deposed Eusthatius as one of the leaders of the Anti-Arian party.

There exists no complete list of Eusebius’ writings (cf. Schwartz); he must have begun to write around the turn of the 3rd to the 4th century. Among his earlier works is the Chronicon, which contains elaborate tables arranged in parallel columns illustrating the world’s history year by year from the birth of Abraham to the year 303 (cf. Schoene, col. 67.69.121-28 on the Median and Achaemenid kings). At the beginning of the period of Christian persecution, Eusebius started a great project of a series of books dealing with the history and philosophy of Christianity and covering the period of Church history from the apostolic age to the reign of Constantine. After having passed through several phases of editing, this Historia ecclesiastica comprised ten books in its final form. Eusebius briefly mentioned Mani, whom he called a “madman,” and his religion, which he considered a “perverse heterodoxy” and “a devil-possessed heresy,” as well as “a deadly poison that came from the land of the Persians” (Hist. eccl. 7.31.1-2). He may have borrowed the story of Mani and other information on the history of Christianity in the region of Mesopotamia from the archives of Edessa. The campaign against Armenia, which the Roman emperor Maximinus Daia started in 312 as an answer to the introduction of Christianity in Armenia by King Tiridates III (Trdat) at the end of the 3rd century, is described in Hist. eccl. 9.8.2-4 (cf. Kettenhofen 1995, pp. 81-84, 103f. on the historical value of this passage). After the death of Constantine the Great (337), Eusebius wrote a book on the emperor’s life, which constitutes an important document on the ecclesiastical activities of this first Christian emperor, despite its panegyrical tone. A long and famous letter of Constantine to Šāpūr II (after 324?) dealing with the fate of Christians in Persia is quoted in Vita Constantini 4.8-13 (ed. Winkelmann; English tr. in Dodgeon and Lieu, pp. 150-52 and p. 380 nn. 13f.).



M. H. Dodgeon and S. N. C. Lieu, The Roman Eastern Frontier and the Persian Wars AD 226-363: A Documentary History, London and New York, 1991; repr. 1994.

Erich Kettenhofen, Tirdād und die Inschrift von Paikuli: Kritik der Quellen zur Geschichte Armeniens im späten 3. und frühen 4. Jh. n. Chr., Wiesbaden, 1995.

K. Lake, ed., Eusebius: The Ecclesiastical History, 2 vols., Cambridge, Mass., 1926-32; repr. Cambridge, Mass., and London, 1973-75.

A. Schoene, ed., Eusebi Chronicorum Libri Duo, 2 vols. in 1, Berlin, 1866-75; repr. Dublin and Zürich, 1967.

E. Schwartz, “Eusebios,” in Pauly-Wissowa, VI/1, cols. 1370-1439.

F. Winkelmann, ed., Über das Leben des Kaisers Konstantin, Berlin, 1975.

(Philip Huyse)

Originally Published: December 15, 1998

Last Updated: January 20, 2012

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