capital, Ctesiphon, with the main Persian army. However, after a few minor skirmishes and sieges Julian arrived with his undefeated army before Shapur II to the walls of Ctesiphon on May 29. Outside the walls a Persian army under Merena was formed up for battle across the Tigris. According to Ammianus Marcellinus, the Persian army featured cataphracts (clibanarii), backed up by infantry in very close order. Behind them there were war elephants. Julian's force attempted to set foot on the opposite shore of Tigris, under harassment by the Persians. After achieving it, the main battle commenced. It was a stunning tactical victory for the Romans, losing only 70 men to the Persians' 2,500 men. One of the Christian sources and not one friendly to the pagan Julian, Socrates Scholasticus, even states that Julian's victories up to this point in the campaign had been so great that they caused Shapur to offer Julian a large portion of the Persian domains if he and his legions would withdraw from Ctesiphon. But Julian rejected this offer out of desire for the glory of taking the Persian capital and defeating Shapur in battle which would earn him the honorific of Parthicus. However, Julian lacked the equipment to lay siege to the strongly fortified Ctesiphon, and the main Sassanid army, commanded by Shapur and far larger than the one just defeated, was closing in quickly. Also critical was the failure of Procopius to arrive with the 18,000 detachment of the Roman army that could have aided Julian in crushing Shapur's approaching force as he had intended. For as previously captured satraps had testified after being fairly treated by Julian, the capture or death of Shapur would have compelled the Persian city to open its gates to the new Roman conqueror. While Julian was in favor of advancing further into Persian territory, he was overruled by his officers. Roman morale was low, disease was spreading, and there was very little forage around. Aftermath Reluctantly, Julian agreed to retreat back along the Tigris and look for Procopius and the other half of his army that had failed to coordinate the double-pincers movement with him outside of Ctesiphon as had been planned. On 16 June 363, the retreat began. Ten days later, after an indecisive Roman victory at Maranga, the army’s rearguard came under heavy attack, in the Battle of Samarra. Not even pausing to put on his