Roman emperor from 306 to 312. His father, the emperor Maximian, abdicated with Diocletian in 305. In the new tetrarchy (two augusti with a caesar under each) that was set up after these abdications, Maxentius was passed over in favour of Flavius Valerius Severus, who was made a caesar, and then, in 306, an augustus. But discontent with the policies of Severus at Rome caused Maxentius to be proclaimed princeps there on Oct. 28, 306, by the Praetorian Guard. In 307 he took the title augustus.
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