This disaster, as may well be imagined, produced an immediate invasion by numberless barbarians, while such multitudes of pretenders to the imperial crown were set up, each asserting his claim by force of arms, that the whole Roman territories were filled with bloodshed and slaughter. At this time Gallienus, the son of Valerian, was the _lawful_ emperor, if indeed we may apply the word to the domination of such a monster. His mode of government may be imagined from the following letter written to one of his officers in consequence of a victory gained over an usurper named _Ingenuus_. “I shall not be satisfied with your putting to death only such as have borne arms against me, and might have fallen in the field: you must in every city destroy all the males, old and young; spare none who have _wished_ ill to me, none who have spoken ill of me, the son of Valerian, the father and brother of princes. _Ingenuus_ emperor! Tear, kill, cut in pieces, without mercy: you understand me; do then as you know I would do, who have written to you with my own hand.” In consequence of this horrible order, not a single male child was left alive in some of the cities of Mœsia, where this inhuman tragedy was acted. In the midst of this dreadful commotion, we find the pestilence contributing its share to the common work of desolation. In Alexandria in Egypt, says Dionysius, bishop of that place, “fury and discord raged to such a degree, that it was more easy to pass from the east to the remotest provinces of the west, than from one place of Alexandria to another. The inhabitants had no intercourse but by letters, which were with the utmost difficulty conveyed from one friend to another. The port resembled the shores of the Red Sea strewed with the carcases of the drowned Egyptians: the sea was dyed with blood, and the Nile choked up with dead bodies. The war was attended with a general famine, and the famine with a dreadful plague, which daily swept off great numbers of people, insomuch that there were then in Alexandria fewer inhabitants, from the age of fourteen to that of eighty, than there used to be from forty to seventy.” It was not in Egypt alone that this calamity prevailed. It raged with great violence in Greece, and at Rome itself; where, for some time, it carried off five thousand persons a day. Many terrible phenomena of nature took place at the same time. The sun was overcast with thick clouds, and great darkness took place for several days, attended with a violent earthquake, and loud claps of thunder, not in the air, but in the bowels of the earth, which opened in several places and swallowed up great numbers of people in their habitations. The sea, swelling beyond measure, broke in upon the continent, and drowned whole cities.[36] [36] Univ. Hist. vol. xvi. pp. 433, 435.