[Sidenote: A.D. 198 (a.u. 951)] [Sidenote:--9--] The next thing Severus did was to make a campaign against the Parthians. While he was busied with civil wars, they had been free from molestation and had thus been able by an expedition in full force to capture Mesopotamia. They also came very near reducing Nisbis, and would have done so, had not Laetus, who was besieged there, preserved the place. Though previously noted for other political and private and public excellences, in peace as well as in wars, he derived even greater glory from this exploit. Severus on reaching the aforesaid Nisibis encountered an enormous boar. With its charge it killed a horseman who, trusting to his own strength, attempted to run it down, and it was with difficulty stopped and killed by many soldiers,--thirty being the number required to stop it; the beast was then conveyed to Severus. The Parthians did not wait for him but retired homeward. (Their leader was Vologaesus, whose brother was accompanying Severus). Hence Severus equipped boats on the Euphrates and reached him partly by marching, partly by sailing. The newly constructed vessels were exceedingly manageable and well appointed, for the forest along the Euphrates and those regions in general afforded the emperor an abundant supply of timber. Thus he soon had seized Seleucia and Babylon, both of which had been abandoned. Subsequently he captured Ctesiphon and permitted his soldiers to plunder the whole town, causing a great slaughter of men and taking nearly ten myriads alive. However, he did not pursue Vologaesus nor yet occupy Ctesiphon, but as if the sole purpose of his campaign had been to plunder it, he thereupon departed. This action was due partly to lack of acquaintance with the country and partly to dearth of provisions. His return was made by a different route, because the wood and fodder found on the previous route had been exhausted. Some of his soldiers made their retreat by land along the Tigris, following the stream toward its source, and some on boats.