The Roman History · Amm. 25.7.12

To which another mischievous and unfair condition was added, that after this treaty was concluded we were not to be at liberty to assist Arsaces against the Persians, if he implored our aid, though he had always been our friend and trusty ally. And this was insisted on by Sapor for two reasons, in order that the man might be punished who had laid waste Chiliocomum at the emperor's command, and also that facility might be given for invading Armenia without a check. In consequence of this it fell out subsequently that Arsaces was taken prisoner, and that, amid different dissensions and disturbances, the Parthians laid violent hands on the greater portion of Armenia, where it borders on Media, and on the town of Artaxata.

Ammianus Marcellinus · translated by C. D. Yonge · 1911 reprint
C. D. Yonge translation (preface dated February 1862); G. Bell and Sons, 1911; Project Gutenberg #28587
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