nued in all probability to be Roman provinces, despite any efforts
that Parthia could have made to recover them. But in August, A.D. 117,
Trajan died; and his successor, Hadrian, was deeply impressed with the
opinion that Trajan's conquests had been impolitic, and that it was
unsafe for Rome to attempt under the circumstances of the time any
extension of the Eastern frontier. The first act of Hadrian was to
relinquish the three provinces which Trajan's Parthian war had added to
the Empire, and to withdraw the legions within the Euphrates. Assyria
and Mesopotamia were at once reoccupied by the Parthians. Armenia
appears to have been made over by Hadrian to Parthamaspates, and to have
thus returned to its former condition of a semi-independent kingdom,
leaning alternately on Rome and Parthia. It has been asserted that
Osrhoene was placed likewise upon the same footing; but the numismatic
evidence adduced in favor of this view is weak; and upon the whole
it appears most probable that, like the other Mesopotamian countries,
Osrhoene again fell under the dominion of the Arsacidae. Rome therefore
gained nothing by the great exertions which she had made, unless it were
a partial recovery of her lost influence in Armenia, and a knowledge of
the growing weakness of her Eastern rival--a knowledge which, though it
produced no immediate fruit, was of importance, and was borne in mind
when, after another half-century of peace, the relations of the two
empires became once more unsatisfactory.

The voluntary withdrawal of Hadrian from Assyria and Mesopotamia placed
him on amicable terms with Parthia during the whole of his reign.
Chosroes and his successor could not but feel themselves under
obligations to the monarch who, without being forced to it by a defeat,
had restored to Parthia the most valuable of her provinces. On one
occasion alone do we hear of any, even threatened, interruption of
the friendly relations subsisting between the two powers; and then the
misunderstanding, whatever it may have been, was easily rectified and
peace maintained. Hadrian, in A.D. 122, had an interview with Chosroes
on his eastern frontier, and by personal explanations and assurances
averted, we are told, an impending outbreak. Not long afterwards
(A.D. 130, probably) he returned to Chosroes the daughter who had been
captured by Trajan, and at the same time promised the restoration of
the golden throne, on which the Parthians appear to have set a spe