Sejanus, Aelius (died 31)

Roman praetorian prefect. He gained great influence over the Roman emperor Tiberius and became chief administrator of the Roman Empire. In AD 23 he was suspected of having procured the poisoning of Drusus, the son of Tiberius by his first wife Vipsania. Thereafter he set about undermining the position of various members of the Emperor's family in order to secure the succession for himself. Tiberius, warned by Antonia, widow of his brother Drusus, at last began to suspect Sejanus's designs on his own imperial power. The Senate decreed his death: he was strangled, and his body, mutilated by the mob, was thrown into the Tiber River. Sejanus was born in Vulsinii, Etruria.