AMMIANUS, Marcellinus, a Roman historian of the 4th century, was born in the city of Antioch, in Syria. In his youth he was enrolled among the protectores domestici, or household guards, which proves him to have been of noble birth. In the year 350 he entered the service of Constantius, the emperor of the East, and, under the command of Ursicinus, a general of the horse, he served during several expeditions. According to his own modest account, it appears that he acquired considerable military fame, and that he deserved well of his sovereign. He attended the Emperor Julian in his expedition into Persia, but it is not known that he obtained any higher military promotion than that which has already been mentioned. He was either in the city or in the vicinity of Antioch when the conspiracy of Theodorus was discovered, in the reign of Valens, and was an eye-witness of the severe tortures to which many persons were subjected by the emperor on that account. But his lasting reputation was not to be acquired from military service. He left the army and retired to Rome, where he employed himself in writing a history of the Roman empire, comprising a period of 282 years. Though a Greek by birth, he wrote in the Latin language; but, according to the remark of Vossius, his Latin shows that he was a Greek, and also a soldier. His history extended from the accession of Nerva to the death of Valens; and the work was originally divided into thirty-one books. Of these the first thirteen have perished, and the eighteen which remain commence with the seventeenth year of the reign of Constantius, and terminate at the year 378. But there are several facts mentioned in the history which prove that the author was alive in the year 380. Of this number are the accession of Theodosius to the ...