Marcus Vinicius (c. 5 BC – AD 46) was twice Roman consul and, as husband of Julia Livilla, grandson-in-law (progener) of the emperor Tiberius.
That same year, Vinicius was requested to take part in the defence of Gnaeus Calpurnius Piso for the murder of Germanicus, but refused.
[8] Vinicius and his nephew, Lucius Annius Vinicianus, were involved in the assassination of the emperor Caligula and, for a short time, even attempted to become his successor to the throne.
[9][10] After Claudius became emperor, Vinicius accompanied him during the Roman conquest of Britain in 43 and was awarded the ornamenta triumphalia.
In 45, he was honoured with the rare distinction of a second consulship as prior consul; his colleague that year was Titus Statilius Taurus Corvinus.