Roman emperor, A. D. 306-307. After the abdication of Diocletian and Maximian, followed by the elevation of Galerius with Constantius Chlorus to the rank of Augusti, it became necessary, in order to maintain the scheme of the empire, to appoint new Caesars [DIOCLETIANUS]. The right of nomination was conceded to Galerius, who selected two creatures of his own, devoted, as he believed, to his interests, Maximinus Daza and Severus. The latter, an obscure Illyrian adventurer, altogether unknown, save as the dissolute, although faithful, adherent of his patron, was invested with the insignia of his new dignity at Milan, on the 1st of May, A.D. 305, by Herculius in person, and obtained Italy, and probably Africa and Upper Pannonia also, as his provinces. But as soon as intelligence was received of the death of Constantius Chlorus, which happened at York, in July, A. D. 306, Severns was forthwith proclaimed Augustus in his stead, by Galerius, and soon after was instructed to quell the disturbances excited by the usurpation of Maxentius. The details of this disastrous campaign, the advance of Severus upon the capital, the defection of his troops, his hasty retreat, and his surrender at Ravenna to Herculius, upon the most solemn assurances of ample protection, have been related in a former article [MAXENTIUS]. In spite, however, of all the promises of the conqueror, the vanquished prince was conveyed as a prisoner of war to the vicinity of Rome, and detained in captivity at Tres Tabernae, on the Appian road, where, upon receiving intimation that he might choose the manner of his death, he opened his veins, and was entombed in the sepulchre of Gallienus, A. D. 307. (Panegr. Vet. i. v.; Auct. De Mort. Persec. 18, 19, 20, 25, 26 ; Victor, de Caes. 40, Epit. 40 ; Eutrop. 10.2; Excerpta Valeslan. 5-10; Zosim. ii, 8, 10.)