The Battle of Solachon was fought in 586 CE in northern Mesopotamia between the East Roman (Byzantine) forces, led by Philippicus, and the Sassanid Persians under Kardarigan. The engagement was part of the long and inconclusive Byzantine–Sassanid War of 572–591. The Battle of Solachon ended in a major Byzantine victory which improved the Byzantine position in Mesopotamia, but it was not in the end decisive. The war dragged on until 591, when it ended with a negotiated settlement between Maurice and the Persian shah Khosrau II (r. 590–628). In the days before the battle, Philippicus, newly assigned to the Persian front, moved to intercept an anticipated Persian invasion. He chose to deploy his army at Solachon, controlling the various routes of the Mesopotamian plain, and especially access to the main local watering source, the Arzamon River. Kardarigan, confident of victory, advanced against the Byzantines, but they had been warned and were deployed in battle order when Kardarigan reached Solachon. The Persians deployed as well and attacked, gaining the upper hand in the centre, but the Byzantine right wing broke through the Persian left flank. The successful Byzantine wing was thrown into disarray as its men headed off to loot the Persian camp, but Philippicus was able to restore order. Then, while the Byzantine centre was forced to form a shield wall to withstand the Persian pressure, the Byzantine left flank also managed to turn the Persians' right. Under threat of a double envelopment, the Persian army collapsed and fled, with many dying in the desert of thirst or from water poisoning. Kardarigan himself survived and, with a part of his army, held out against Byzantine attacks on a hillock for several days before the Byzantines withdrew. Background In 572 the Byzantine ruler Justin II (reigned 565–578) refused to renew the annual payments to Sassanid Persia that had been part of the peace agreement concluded by his uncle, Justinian I (r. 527–565) and the Persian shah Khosrau I (r. 531–579) in 562. This marked the culmination of the progressive deterioration of Byzantine–Persian relations over the previous years, which manifested itself in diplomatic and military manoeuvring in their geopolitical periphery. Thus the Byzantines initiated contacts with the Central Asian Göktürks for a joint effort against Persia, while the Persians intervened in Yemen against the Christian Axumites, allies of Byzantium. Justin furthermore regarded the annual tribute as an indignity unworthy of Romans, and