Sejanus: Greed, Ruthlessness and Ruin

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Tacitus is not sparing with his moralistic tendencies when writing his Annals. He argues that the “principal responsibility’ of history is to “prevent virtues from being silenced and so that crooked words and deeds should be attended by the dread of posterity and infamy.” But it is the latter which seems to be favoured in his writing. It is exactly this that Tacitus’ himself provides in his work – a record of the misdeeds of the power-hungry and immoral, such that later opportunists may think twice before acting. Tacitus criticises the concentration of power on the state by analysing its corrupting influences, and no-one exemplifies this like Sejanus.

Lucius Aelius Sejanus plays a central role in Book IV of Tacitus’ Annals. In the power vacuum created by Augustus’ death, Tiberius struggled to maintain a smooth transition of power. Tiberius lacked Augustus’ public authority and was forced to act immediately to demonstrate and secure his power. However, this increasingly febrile situation in Rome created the perfect opportunity for opportunists like Sejanus to climb the political ladder.

Sejanus had been born into the equestrian family (one rank below Senator) of Lucius Seius Strabo in 20 B.C. Sejanus had gradually increased his influence in the capital through debasement and “struprum” (illicit sex) with more powerful nobles. Tacitus variously describes Sejanus as “audacious,” “secretive” and harbouring “an unbounded lust for power” and the developing narrative is carefully crafted to show the very worst of Sejanus’ flaws.

Strabo had initially been appointed Prefect of the Praetorian Guard under the reign of Augustus. This position very much marked the pinnacle of success in the public career of a Roman equestrian and granted significant influence over the military. As the Praetorian Guard was specially appointed as a bodyguard to the Emperor (as well as keeping the peace in Rome), the opportunity for large-scale corruption and bribery was ever present. Following Strabo’s death, Sejanus took up this position, which gave him direct access to Tiberius. The Emperor would be easy prey to Sejanus’ plotting.

Sejanus began by increasing the Guard’s power. Tiberius, perhaps wary of their influence, had scattered the Praetorian Guard throughout the city and limited them to nine cohorts. Sejanus took steps to undo these measures and increased the size of the force by three cohorts, unified the soldiers into one centralised military camp just outside of Rome and assumed sole control over the Guard (previously it had been divided across two Prefects). His deception was not recognised by the Emperor who proclaimed him the “partner of my labours” and built statues in his honour.

However, Sejanus’ position was threatened by Drusus, Tiberius’ son and heir to the Imperial Throne. Drusus openly complained about Sejanus’ influence within Rome and resented the power of this ‘equestrian.’ Sejanus thus resolved to murder Drusus. At first, he seduced Livilla, Tiberius’ daughter-in-law and the wife of Drusus. Whilst this did mean that he was cheating on his wife, Apicata, Sejanus was driven more by his pursuit of power than any illusion of familial loyalty. Having persuaded Livilla of the need to remove Drusus, he had Tiberius’ heir poisoned by the eunuch Lygdus in A.D. 23. He was so precise and careful in his crime that his perfidy was only discovered eight years later, after Sejanus’ downfall.

However, this is not the only rumour surrounding Drusus’ death: indeed, Tacitus suggests a far more malevolent account of Sejanus’ poisoning of Drusus. Reportedly, Sejanus warned Tiberius, who was attending a banquet at Drusus’ house, that his heir was planning to poison him. Trusting Sejanus implicitly, Tiberius then passed his cup over to Drusus, who was forced to drink it in front of his adopted father. As Drusus died shortly afterwards (albeit due to the poison administered by Lygdus) Tiberius was thus assured of Sejanus’ intelligence and loyalty to the Imperial House. Whilst Tacitus does recognise that this rumour is unverifiable and likely false, it is certainly indicative of Sejanus’ arrogance and lack of empathy.

Since this first obstacle from the throne had now been removed, Sejanus then realised that he would need to eliminate the children of Germanicus, who were next in line as Tiberius’ heirs. Realising that it would be impractical to poison all three of Germanicus’ sons, Sejanus instead chose to slander their mother, Agrippina. He hoped that Tiberius would no longer consider the children worthy to inherit the throne due to the ‘misdemeanours’ of their mother. In this he succeeded. Tiberius grew increasingly resentful of two of Germanicus’ son, Nero Caesar and Drusus Caesar, and warned the Senate to beware the “conceit” of these youths. However, by distancing himself from the family of Germanicus, Tiberius found himself increasingly isolated and reliant upon Sejanus, who was edging towards the zenith of his power.

It was at this point, though, that Sejanus overstepped his bounds. He asked Tiberius for permission to marry Livilla (Drusus’ widow). Tiberius, despite praising Sejanus’ loyalty, callously refused his request, on the grounds that a member of the Imperial Household ought not to marry a mere “knight.” Rebutted by the Emperor, Sejanus returned to his secret machinations and continued to spread rumours of Agrippina’s treachery.

Nonetheless, Sejanus was soon able to return to the Emperor’s favour. Whilst dining at a cavern near Amyclae with Tiberius, a sudden rockslide placed the pair in danger. Whilst other bystanders fled, terrified, Sejanus resolutely protected the Emperor, bracing himself in front of the “boulders.” Not only did Sejanus remain unharmed, but he also regained Tiberius’ admiration and trust. His newly restored power allowed him to weave further enmity between Tiberius and Germanicus’ children.

By this point Sejanus enjoyed great respect in Rome (or, at least, had sycophants vying for his political support), and his position was only improved when Tiberius, exhausted and tired of politics, retired to Capri in A.D. 26, never again to return to Rome. Sejanus thus became the intermediary between Rome and the Emperor and controlled the flow of information between the two. Sejanus strengthened his position further in a serious of face trials and false accusations of treasons of his opponents. Titus Sabinus, a Roman Knight, was executed due to his friendship with Germanicus. Agrippina was accused of “insubordinate language” and “disobedient spirit” whilst Nero Caesar was charged with “homosexual indecency.” Many of his adversaries, fearful of persecution, committed suicide.

In A.D. 31, Sejanus was granted shared consulship with Tiberius. Since Tiberius was indefinitely absent, Sejanus had become Emperor in all but name. Cassius Dio comments that Sejanus “seemed to be the Emperor” whilst “Tiberius [was] a kind of island potentate.” Tacitus goes further, dismissively stating that the Emperor spent his time at Capri “in secret orgies, or idle malevolent thoughts.”

However, this prosperity did not last long for Sejanus. Tiberius grew wary of his growing influence and leapt to action. Fearing that Sejanus would attempt a coup, Tiberius knew that he could not send a letter outright condemning him to the Senate. Instead, he caused great confusion by sending contradictory letters to the Senate regarding his health and opinions of Sejanus, resulting in a withdrawal of many of his followers, who now deemed it unprofitable to continue in their allegiance during this time of uncertainty. Tiberius then sent a final letter to the Senate denouncing Sejanus and ordering his immediate execution without trial. The commands were obeyed, and Sejanus, who, only moments ago, had been merely a formality away from Emperor, was treated like a “runaway slave.” He was strangled and his body cast down the Gemonian Stairs – a sign of disrespect. Apicata, although absolved of any culpability in Drusus’ murder, killed herself. Livilla also died, possibly starved to death by her mother, Antonia.

Tacitus warns of the devastating consequences of power concentrated in the hands of a few individuals and Sejanus is a prime case study the vicious opportunism, censorship and sycophancy that such an atmosphere cultivates. His disgust is particularly pronounced at this equestrian Prefect, who is accused of corruption, sexual immorality and greed power – a clear display of horror at a political system which was only being repeated at the time Tacitus was writing under the reign of Domitian.


Cassius Dio, Roman History

Cornelius Tacitus. Annals.