Note: Do not rely on this information. It is very old.
Ammianus Marcellinus
Ammianus Marcellinus, a Latinised Greek, who, after serving as a soldier under Constantine and Julian, settled in Rome, and wrote his great work Rerum Gestarum Libri XXXI, covering the period from Nerva's accession to the death of Valens (96-378 A.D.). Only 18 books are extant. Gibbon praises the author for accuracy, and his moderation in dealing with the development of Christianity is remarkable. He died about 390.