After the internal troubles were in some measure pacified, and Gordian III., almost still a boy, under the protection of the commandant of Rome and soon of his father-in-law Furius Timesitheus, bore undisputed sway in the whole empire, war was solemnly declared against the Persians, and in the year 242 a great Roman army advanced under the personal conduct of the emperor, or rather of his father-in-law, into Mesopotamia. It had complete success; Carrhae was recovered, at Resaina between Carrhae and Nisibis the army of the Persian king Shahpuhr or Sapor (reigning 241-272), who shortly before had followed his father Ardashir, was routed, and in consequence of this victory Nisibis was occupied. All Mesopotamia was reconquered; it was resolved to march back to the Euphrates, and thence down the stream against the enemy’s capital Ctesiphon. Unhappily Timesitheus died, and his successor, Marcus Julius Philippus, a native of Arabia from the Trachonitis, used the opportunity to set aside the young ruler. When the army had accomplished the difficult march through the valley of the Chaboras towards the Euphrates, the soldiers in Circesium, at the confluence of the Chaboras with the Euphrates, did not find--in consequence, it is alleged, of arrangements made by Philippus--the provisions and stores which they had expected, and laid the blame of this on the emperor. Nevertheless the march in the direction of Ctesiphon was begun, but at the very first station, near Zaitha (somewhat below Mejadîn), a number of insurgent guards killed the emperor (in the spring or summer of 244), and proclaimed their commandant, Philippus, as Augustus in his stead. The new ruler did what the soldiers or at least the guardsmen desired, and not merely gave up the intended expedition against Ctesiphon, but led the troops at once back to Italy. He purchased the permission to do so from the conquered enemy by the cession of Mesopotamia and Armenia, and so of the Euphrates frontier. But this conclusion of peace excited such indignation that the emperor did not venture to put it in execution, and allowed the garrisons to remain in the ceded provinces.[82] The fact that the Persians, at least provisionally, acquiesced in this, gives the measure of what they were then able to do. It was not the Orientals, but the Goths, the pestilence that raged for fifteen years, and the dissensions of the corps-leaders quarrelling with one another for the crown, that broke the last strength of the empire. [Sidenote: Palmyra.]