AMMANUS, Marcellinus. — A Latin pagan historian of the 4th century, born at Antioch into a noble family. The year of his birth is unknown, but it may be placed around 335; likewise, nothing is known of his life until 353, when he was enrolled in the corps of protectores domestici, under the command of the magister equitum Ursicinus, whom A. would follow faithfully until his dismissal. In 353, together with Ursicinus, he moved from Nisibis to Antioch, where the latter had been summoned by the Caesar Gallus to preside over the trial of the city’s leading citizens; in 354 he went to Milan, where an imperial order from Constantius had instructed Ursicinus to present himself to answer the suspicions weighing upon him. He followed Ursicinus also into the Gauls, where the latter had been sent to suppress the revolt of the usurper Silvanus, and then again to the East when the Persians violated the empire’s borders. A. took part in both these campaigns.
Noteworthy is his account of the campaign against the Persians (Books XIX–XX), particularly the siege of Amida, where he had taken refuge (359). After the city was captured, A. and Ursicinus escaped to Mytilene and then to Antioch, but the failure led to Ursicinus’s dismissal (360).
In 363 we find A. again in Persia, at the side of the Emperor Julian, who on 26 July of that year met his death on the battlefield. After the peace concluded by Jovian with the Persians, A. seems to have definitively laid down his arms and retired to private life, first at Antioch, then, after visiting various regions including Egypt and Greece, at Rome, where he devoted himself to composing his great historical work, a continuation of the Histories of Tacitus. Whether in this final period of his life he held some civil magistracy remains conjectural, while it is certain that the soldier gave way to the scholar. Libanius (Epist. 983) in 391 still recalls him in Rome, where he received the public acclaim for a reading of his Rerum gestarum libri. After that year, no further news of him survives.
The complete Rerum gestarum libri numbered thirty-one, almost all certainly written before 400. Only the last eighteen have come down to us. The chronological limits of the narrative are indicated by A. in the conclusion of the work: «Haec ut miles quondam et graecus, a principatu Caesaris Nervae exorsus ad usque Valentis interitum pro virium explicavi mensura» (Book XXXI), that is, from the reign of Nerva—where Tacitus’s narrative ends—down to the death of Valens (364–378).
The first thirteen lost books, together with the preserved portion of Book XIV, carried the narrative to the death of the Caesar Gallus (354), treated rather briefly, as less familiar to A., largely compiled from pre-existing documents. Books XV–XXV contain the events from Julian’s appointment as Caesar to the death of Jovian (355–364). The remaining books are devoted to the events from the accession of Valentinian to the death of his brother Valens (364–378). The full narrative of the surviving books is largely the fruit of the author’s personal experience.
Among all pagan historians, A. is certainly the only one to treat Christianity at length, and his testimony is valuable for Church history because it is contemporary with the events narrated, credible in its pursuit of truth, and of greater worth because its author was not a Christian. The assertion of C. Chifflet that A. was a Christian lacks foundation, and his paganism is proven by his entire work. Yet A.’s religion was not that of the ancient Greeks and Romans; he did not believe in the gods of Olympus, whose existence he denies, but in a God who is not a person but a force governing all things. His religious conception closely approaches that of the Neoplatonists, from whom he drew the religious freedom that allows each person to follow his own conscience. He indeed showed benevolent tolerance toward all religions and did not attack Christianity as other pagan writers had done; on the contrary, he appreciated Christian doctrines and professed admiration for the heroism of the martyrs, even going so far as to criticize the zeal of his hero Julian.
Christian historians of antiquity and the Middle Ages, with due exceptions, generally ignored A. and his work solely because he was a pagan, whereas he deserves a distinct place among the sources for the history of the ancient Church, of which he remains an impartial witness.
The manuscripts of A.’s work preserved are no older than the 9th or 10th century. The editio princeps appeared in Rome in 1474 and was the work of A. Sabinus. Among later editions, those of E. de Valois (Paris 1636) and J. A. Wagner (Leipzig 1808) deserve mention for their valuable commentaries. The most recent edition is that of C. Clark (2 vols., Berlin 1910–15).