The Ἐκκλησιαστικὴ ἱστορία of Eusebius, bishop of Caesarea, is a 4th-century work giving a chronological account of the development of Xianity from the 1st century to the 4th. It was written in Koine Greek & survives also in Latin, Syriac & Armenian mss. It was the 1st full-length historical narrative written from a Xian viewpoint. In the early 5th century two advocates in Constantinople, Socrates Scholasticus & Sozomen, & a bishop, Theodoret of Cyrrhus, Syria, wrote continuations, establishing the convention of continuators that would determine to a great extent the way history was written for the next 1000 years. Eusebius' attempt to lay out a comparative timeline of pagan & Old Testament history set the model for the other historiographical genre, the medieval chronicle or universal history. Eusebius had access to the Theological Library of Caesarea & made use of ecclesiastical monuments & documents, acts of the martyrs, letters, extracts from earlier Xian writings, lists of bishops etc, often quoting the originals at length so his work contains materials not elsewhere preserved. For example he wrote that Matthew composed the Gospel according to the Hebrews & his Church Catalog suggests it was the only Jewish gospel. It's therefore of historical value, tho it pretends neither to completeness nor to the observance of due proportion in the treatment of the subject-matter. Nor does it present in a connected & systematic way the history of the Church. It's to no small extent...
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