Roman emperor. Legate of the fourth legion on the Euphrates and later governor of Upper Pannonia. Proclaimed emperor by the Danube legions in 193. At the battle near Lyons in 197, he conquered his rival Albinus. Severus laboured to reorganize the Empire on the model of an Oriental despotism, and favoured the provinces rather than Italy, basing his power on the Preatorian Guard. The fifth persecution of the Christians broke out during his reign.