From Callinicus the emperor marched along the course of the Euphrates to Circusium, or Circesium, at the junction of the Khabour with the Euphrates, arriving at this place early in April.  Thus far he had been marching through his own dominions, and had had no hostility to dread.  Being now about to enter the enemy’s country, he made arrangements for the march which seem to have been extremely judicious.  The cavalry was placed under the command of Arinthseus and Prince Hormisdas, and was stationed at the extreme left, with orders to advance on a line parallel with the general course of the river.  Some picked legions under the command of Nevitta formed the right wing, and, resting on the Euphrates, maintained communication with the fleet.  Julian, with the main part of his troops, occupied the space intermediate between these two extremes, marching in a loose column which from front to rear covered a distance of above nine miles.  A flying corps of fifteen hundred men acted as an avant-guard under Count Lucilianus, and explored the country in advance, feeling on all sides for the enemy.  The rear was covered by a detachment under Secundinus, Duke of Osrhoene, Dagalaiphus, and Victor.

Having made his dispositions, and crossed the broad stream of the Khabour, on the 7th of April, by a bridge of boats, which he immediately broke up, Julian continued his advance along the course of the Euphrates, supported by his fleet, which was not allowed either to outstrip or to lag behind the army.  The first halt was at Zaitha, famous as the scene of the murder of Gordian, whose tomb was in its vicinity.  Here Julian encouraged his soldiers by an eloquent speech, in which he recounted the past successes of the Roman arms, and promised them an easy victory over their present adversary.  He then, in a two days’ march, reached Dura, a ruined city, destitute of inhabitants, on the banks of the river; from which a march of four days more brought him to Anathan, the modern Anah, a strong fortress on an island in the mid-stream, which was held by a Persian garrison.  An attempt to surprise the place by a night attack having failed, Julian had recourse to persuasion, and by the representations of Prince Hormisdas induced its defenders to surrender the fort and place themselves at his mercy.  It was, perhaps, to gall the Antiochenes with an indication of his victorious progress that he sent his prisoners under escort into Syria, and settled them in the territory of Chalcis, at no great distance from the city of his aversion.  Unwilling further to weaken his army by detaching a garrison to hold his conquest, he committed Anathan to the flames before proceeding further down the river.