Biography -- By Sara Wijma
The little that is known about Ammianus Marcellinus is mostly derived from autobiographical references in his Res Gestae. The one explicit indication about his life is at the end of his work where he tells us he was a soldier and a Greek (31.16.9: miles quondam et Graecus). In his extant narrative he also tells us he was an adolescens in A.D. 357 (16.10.21). So Ammianus Marcellinus must have been born sometime before 335 in Greece. Matthews (1989) even suggest a date as early as 325.
Further information about his background is often derived from a letter written by Libanius to a fellow-Antiochene in Rome, called Marcellinus (Epist. 1063). Up till today there is a discussion whether the recipient of this letter was Ammianus Marcellinus, author of the Res Gestae. In the letter, dated in late 392 by Seeck (1894), Libanius congratulates Marcellinus with his literary achievement during his stay in Rome (There is also discussion about the interpretation of the Greek word suggraphè, which could mean both literary and historical literary achievement; Matthews 1994). According to the traditional view the letter was adressed to (our) Ammianus Marcellinus; hence Ammianus is considered to be a native of Antioch. Recently this view - defended by Matthews 1989 and 1994 - has been challenged by a number of historians.
Bowersock (1990) doesn't agree with Matthews that the recipient of the letter was Ammianus, and that therefore Ammianus did not necessarily come from Antioch. Bowersock suggests Alexandria instead. Fornara (1992) agrees with Bowersock that the recipient was not Ammianus, but he suggests Ammianus came from Thessalonica. Also Barnes (1998) doesn't fully believe in Ammianus as the recipient but he agrees with Matthews on his Syriac origin since Ammianus spoke Syriac (18.8.20-21). According to Barnes, he may have come from either Tyre or Sidon or even Antioch.
The remarks in the Res Gestae on how well Ammianus knew Antioch and how much he admired the city (14.8.8 : `Antioch `ennobles' Syria') are no convincing evidence for concluding that Ammianus was a native from that city. However, he might have lived there from 363 to 378.
About his social background nothing conclusive can be said, but the fact that he was an elite officer as well as his attitude towards certain economic and social problems suggests a curial background. Ammianus strongly denounces Julian's policy of cutting down some privileges of the curiales (12.9.12 and 14.4.21). The implicit self-reference is hard to miss and might mean that Ammianus himself was affected by these measures.
Some time before 353, when Ammianus was in his twenties, he joined the army and was made protector domesticus attached to the staff of Ursicinus, the master of the cavalry in the East. Most of the time this rank of protector domesticus, elite officers, was reserved for sons of military officers of high rank. So Ammianus probably belonged to a family of high, probably, curial rank, since he was too young to have built up a glorious military career and get promoted to the position he held. There is also a reference in the Res Gestae to suggest his curial rank. He tells us that "I was now overcome with excessive walking, to which as a gentleman (ingenuus) I was not accustomed" (19.8.6).