Zosimus, New History — Book the Third (1814)
“ Notwithstanding the Romans suffered all these disasters they did not lose even one of those provinces. When the republic was changed into a monarchy, and Augustus constituted the Tigris and Euphrates the boundary of the Roman empire, even that circumstance did not deprive them of this country. On the contrary, a considerable time afterwards, when the emperor Gordianus fought against the Persians, and lost his life in the midst of the enemy’s country, the Persians, even after that disaster, were not able to acquire any part of the Roman dominion. ”
