interposed between the Persians and their longed-for prey, Belisarius having fixed his headquarters at Chalcis, half a degree to the west of Gabbula, and twenty-five miles nearer to Antioch.  Thus balked of their purpose, and despairing of any greater success than they had already achieved, the allies became anxious to return to Persia with the plunder of the Syrian towns and villages which they had sacked on their advance.  Belisarius was quite content that they should carry off their spoil, and would have considered it a sufficient victory to have frustrated the expedition without striking a blow.  But his army was otherwise minded; they were eager for battle, and hoped doubtless to strip the flying foe of his rich booty.  Belisarius was at last forced, against his better judgment, to indulge their desires and allow an engagement, which was fought on the banks of the Euphrates, nearly opposite Callinicus.  Here the conduct of the Roman troops in action corresponded but ill to the anxiety for a conflict.  The infantry indeed stood firm, notwithstanding that they fought fasting; but the Saracenic Arabs, of whom a portion were on the Roman side, and the Isaurian and Lycaonian horse, who had been among the most eager for the fray, offered scarcely any resistance; and, the right wing of the Romans being left exposed by their flight, Belisarius was compelled to make his troops turn their faces to the enemy and their backs to the Euphrates, and in this position, where defeat would have been ruin, to meet and resist all the assaults of the foe until the shades of evening fell, and he was able to transport his troops in boats across the river.  The honors of victory rested with the Persians, but they had gained no substantial advantage; and when Azarethes returned to his master he was not unjustly reproached with having sacrificed many lives for no appreciable result.  The raid into Syria had failed of its chief object; and Belisarius, though defeated, had returned, with the main strength of his army intact, into Mesopotamia.  The battle of Callinicus was fought on Easter Eve, April 19.

Azarethes probably reached Ctesiphon and made his report to Kobad towards the end of the month.  Dissatisfied with what Azarethes had achieved, and feeling that the season was not too far advanced for a second campaign, Kobad despatched an army under three chiefs, into Mesopotamia, where Sittas was now the principal commander on the Roman side, as Belisarius had been hastily summoned to Byzantium in order to be employed against the “Vandals” in Africa.  This force found no one to resist in the open field, and was therefore able to invade Sophene and lay siege to the Roman fortress of Martyropolis.  Martyropolis was ill provisioned, and its walls were out of repair.  The Persians must soon have taken it, had not Sittas contrived to spread reports of a diversion which the Huns were about to make as Roman allies.  Fear of being caught between two fires paralyzed the Persian commanders; and before events undeceived them, news arrived in the camp that Kobad was dead, and that a new prince sat upon the throne.  Under these circumstances, Chanaranges, the chief of the Persian commanders, yielded to representations made by Sittas, that peace would now probably be made between the contending powers, and withdrew his army into Persian territory.