The only explicit indication in the text of Ammianus Marcellinus as to the historian's origin comes in the famous epilogue to the Res Gestae, that he had written ‘as once a soldier, and a Greek’ , supported by various passages in which he refers to the Greek language as his own. The evidence that, through the length and breadth of the Greek-speaking world, we should look to Syrian Antioch for his place of origin, is provided by the orator of that (...) city, Libanius, in a letter written late in 392 ‘to Marcellinus’. The purpose of this article is to set out explicitly the arguments for the identification of Libanius' correspondent as Ammianus Marcellinus in the light of the recent challenges to the accepted view offered by G. W. Bowersock, C. W. Fornara, and T. D. Barnes. Since the discussion requires that the letter be considered in detail, it is given here, in Foerster's Teubner text followed by a translation of Libanius' often very allusive language. (shrink)