Nero had taken a relatively relaxed view of military matters. Whereas other emperors had sought to keep major commands within the imperial family and been cautious about creating powerful generals, Nero seems to have been unconcerned as to the loyalty of his generals and the troops until near the end of his reign. He gave considerable independence and power to Corbulo on the Eastern frontier. But the suppression of the Boudiccan revolt also required major military intervention. But in late 66, the situation changed.
Suetonius (Nero 36) has a conspiracy of Vinicius (or Vinicianus), which must date to after the death of Thrasea and probably to 66 or 67. It was discovered at Brundisium and probably related to Nero’s journey to Greece. Annius Vinicianus had arrived in Rome as escort to Tiridates (prospective King of Armenia) in 66 (Dio, 62. 23). He was Corbulo’s son-in-law and had been serving with Corbulo in the East. Vinicianus was likely the brother of Annius Pollio, who was exiled for involvement in the Pisonian conspiracy. He was also married to Servilia, daughter of Borea Soranus. His involvement in a conspiracy implicated Corbulo.
We are used to a division between political and military groups. Such a division was foreign to Roman culture. There were some men who had extensive military careers and others who never went close to the army, but these were drawn from the same social circle and neither socially or culturally was there a marked division between military men and civilian leaders. Corbulo, the leading general, was closely tied to the leading figures in Rome’s political elite.
Corbulo’s mother was Vistilia, who had a six husbands and seven children. Several of Corbulo’s brothers went on to high office and his half-sister became Caligula’s mistress. He married a Longina. She was likely the daughter of the Cassius put to death by Nero in 66. The family could trace a link back to Augustus. Of his two daughters, one married Vinicianus, the other was married to an Aelius Lamia and then to Domitian, future emperor and son of Vespasian.
Corbulo was closely related by marriage and through extended familial ties to many of the leading figures of Roman society and throughout 65 and 66 these people were being arrested, exiled or killed.
Nero summoned Corbulo to join him in Greece together with the governors of the two Germanies, Sulpicius Scribonius Rufus and Sulpicius Scribonius Proculus, who were brothers. All three were were condemned when they arrived (Dio, 63. 17).
It is difficult to believe that they expected their condemnation. These were three of the most powerful individuals in the state, who had shown loyalty for extended periods. Nero must have feared some sort of military conspiracy. In retrospect, one can see how the connections of conspirators and victims of Nero’s purges were creeping closer and closer to Corbulo. The precise charge hardly matters.
The death of Corbulo illustrates the catastrophic decline of the regime. The Roman aristocracy was closely interlinked. Once one suspected one element of a social network, another element also came under suspicion. If one killed a prominent Roman senator, how would his family and friends react? If one was emperor, should one remove a potential threat just to be safe? Once the killing started, how does one stop it? If Corbulo was victim, who would be next?
But if these were the quandaries of the emperor, everyone could also reconstruct his thinking. Who was not at risk? Who might mourn Nero’s death?
The stage was set for the final act.