Sejanus

• 1. Introduction

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  Sejanus died on the 18th of October, AD 31, strangled by order of the same emperor he had served for seventeen years. His body was thrown down the Gemonian stairs, a public staircase in Rome reserved for displaying the corpses of condemned criminals. By the time that happened, Sejanus had shared the consulship with the Emperor Tiberius, commanded an army of around 12,000 soldiers, and held Rome so firmly in his grip that senators courted his favor as if he were emperor himself. Then, within hours, it was over.

  How does a man of equestrian birth, a rank below the senatorial class, rise to become the second most powerful person in the Roman Empire? How did he reshape a bodyguard unit into a political force that would outlast him by centuries? And what exactly caused his sudden fall? Those are the questions this documentary will follow, through one of the most dramatic careers in Roman history.

• 2. Roots and Family

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  Sejanus was born around 20 BC at Volsinii, in Etruria, into the Seia gens. His father was Lucius Seius Strabo, a man of the Equites class, which was the second-highest social class of the Roman Republic and early Empire, just below the Senate.

  The family had built careful connections through strategic marriages. Sejanus’s grandfather had tied the Seii to senatorial families through his marriage to Terentia, who was a sister of the wife of Gaius Maecenas. Maecenas was one of Emperor Augustus’s most powerful political allies, and that link placed the Seii within reach of the imperial orbit.

  The question of Sejanus’s own mother is contested. He was once thought to be a child of his father’s marriage to Cosconia Gallita, whose brothers both held suffect consulships. But the historian Ronald Syme argued that Sejanus’s mother was a Junia Blaesa, sister of Junius Blaesus. Blaesus would later distinguish himself as a military commander, becoming proconsul of Africa in AD 21 and earning triumphal honors for crushing the rebellion of Tacfarinas.

• 3. Reshaping the Guard

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  Lucius Seius Strabo was appointed prefect of the Praetorian Guard sometime after 2 BC, and his son Sejanus likely accompanied Gaius Caesar, the adopted son of Augustus, during campaigns in Armenia in 1 BC. When Augustus died in AD 14, Strabo was assigned to the governorship of Egypt and Sejanus became sole commander of the Praetorians at his father’s side. Within a year, Strabo was gone and Sejanus commanded alone.

  Augustus had created the Praetorian Guard in 27 BC as an elite imperial bodyguard. He kept it deliberately modest in profile: nine cohorts, one fewer than a standard Roman legion, scattered across lodging houses throughout the city, commanded by two prefects. The republican veneer mattered to Augustus; the guard was a power hidden in plain sight.

  Sejanus stripped away the camouflage. In AD 20, he moved the dispersed encampments into a single garrison just outside Rome, the Castra Praetoria, and increased the number of cohorts from nine to twelve. He abolished the practice of shared command between two prefects and personally appointed the centurions and tribunes. By AD 23, around 12,000 soldiers were under his direct command, all at his immediate disposal. Tiberius no longer bothered to maintain Augustus’s republican pretense; he openly displayed the strength of the guard at public parades.

  These changes had an impact that outlasted Sejanus’s career by centuries. The founding of the Castra Praetoria established the Praetorian Guard as the political force for which it is primarily known today. Maecenas had once warned Augustus that it was dangerous to allow one man to command the guard. In the event of AD 31, Tiberius was forced to rely on the vigiles, the city’s police and fire service, precisely because his own guard could no longer be trusted.

• 4. Eliminating Drusus

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  Tiberius called Sejanus “Socius Laborum,” meaning my partner in my toils, a title that by AD 23 carried real weight. Sejanus had been raised to the rank of praetor, a position not normally open to men of equestrian class. Statues honoring him stood in the Theatre of Pompey. His followers were advanced to public offices and governorships across the empire.

  This prominence bred specific enemies. Tiberius’s son Drusus Julius Caesar had served alongside Sejanus in AD 15 when both were sent to quell a mutiny among legions in Pannonia. Drusus restored stability, put the chief instigators to death publicly, and returned the legions to their winter barracks. The mission succeeded, but the years that followed brought growing animosity between the two men.

  By the early AD 20s, Drusus had been openly groomed as successor, sharing the consulship with Tiberius in AD 21 and commanding legions in Illyricum in AD 18. In practice, Sejanus was still the second man in Rome. Seeking to bind himself to the imperial family, he arranged a betrothal between his daughter Junilla, who was just four years old, and the son of Claudius. The boy died a few days later, by asphyxiation, before the marriage could take place.

  Sejanus then turned toward a more direct approach. By AD 23 the enmity between Drusus and Sejanus had reached a breaking point; Drusus had actually struck the prefect with his fist and complained openly that a stranger had been invited to assist in governing while the emperor’s son was alive. Sejanus seduced Drusus’s wife Livilla and, with her as an accomplice, had Drusus slowly poisoned. Drusus died of apparently natural causes on the 13th of September, AD 23. The truth would not emerge until after Sejanus himself was dead, when Apicata’s letter to Tiberius and confessions extracted under torture from Livilla’s slaves revealed what had been done.

• 5. Tiberius in Retreat

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  Drusus’s death left Tiberius personally devastated and politically exposed. He had been sharing tribunician powers with his son since AD 22, preparing to pass responsibilities forward. With that plan destroyed, the emperor leaned more heavily on Sejanus and turned his attention to the sons of Germanicus, who had died in AD 19 in suspicious circumstances in Syria, as possible heirs.

  Germanicus’s widow, Agrippina the Elder, had returned to Rome with her six children and aligned herself with senators who opposed Sejanus. Her relationship with Tiberius corroded steadily; she believed openly that he bore responsibility for Germanicus’s death. Tiberius’s mother Livia Drusilla, widow of Augustus, also held her in contempt, partly because Agrippina’s ambition to be the mother of emperors was no secret in Rome. Sejanus watched Agrippina’s sons Nero, Drusus, and Caligula with concern.

  In AD 25, Sejanus asked to marry Livilla. Tiberius refused, warning him he risked overstepping his rank. That rebuke alarmed Sejanus and redirected his strategy. He fed Tiberius’s existing paranoia about Agrippina and the Senate until the emperor first withdrew to the countryside of Campania in AD 26, then retreated entirely to the island of Capri, where he would remain until his death in AD 37. From Capri, Tiberius communicated with Rome only through Sejanus, who controlled all information passing between the island and the capital.

  Liby Drusilla’s death in AD 29 removed the last constraint on Sejanus. Tacitus records that her presence had quietly checked his most overt moves. Without her, Sejanus launched a series of purge trials targeting senators and wealthy equestrians. Networks of spies and informers brought accusations of treason. Many chose suicide rather than face condemnation. The prominent senator Gaius Asinius Gallus was among those who perished. Agrippina, Nero, and Drusus were arrested and exiled in AD 30; they later starved to death in suspicious circumstances. Only Caligula survived, by moving to Capri with Tiberius in AD 31, along with Germanicus’s three daughters, Agrippina the Younger, Drusilla, and Livilla.

• 6. The Fall

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  In AD 31, Sejanus shared the consulship with Tiberius, who had not set foot in Rome since AD 26. He finally became betrothed to Livilla. Senators and equestrians celebrated his birthday publicly and raised statues in his honor. The historian Cassius Dio wrote that Sejanus himself seemed to be the emperor and Tiberius a kind of island potentate.

  The information that broke this arrangement came through an unexpected channel. According to Josephus, it was Antonia, the mother of Livilla, who sent a letter to Capri alerting Tiberius to the threat Sejanus posed. She dispatched the letter in the care of her freedman Pallas, possibly carrying information provided by a man named Satrius Secundus. A letter from Capri then ordered, according to Juvenal, that Sejanus be executed without a trial.

  But Tiberius was careful. He understood that an outright condemnation could provoke Sejanus to attempt a coup. His response was a sequence of deliberately contradictory letters to the Senate, some praising Sejanus and some denouncing him, sometimes announcing his own imminent return to Rome and sometimes claiming to be near death. He stepped down as consul, forcing Sejanus to do the same. He conferred an honorary priesthood on Caligula, which rekindled popular support for the house of Germanicus. Tiberius’s intentions became unreadable, and Sejanus’s followers began quietly withdrawing their support.

  Once Tiberius judged that backing for Sejanus was weaker than he had feared, he moved. He chose Naevius Sutorius Macro, who had been prefect of the vigiles, to replace Sejanus. On the 18th of October, AD 31, Sejanus was summoned to a Senate meeting by a letter from Tiberius, ostensibly to receive the tribunician powers. He arrived at dawn. While the letter was being read to the Senate, and as senators initially congratulated Sejanus on what they assumed was a promotion, Macro took control of the Praetorian Guard. Members of the vigiles, led by Publius Graecinius Laco, surrounded the building. When the letter abruptly denounced Sejanus and ordered his arrest, he was taken immediately and imprisoned in the Tullianum. That same evening the Senate condemned him to death. He was strangled and his body cast down the Gemonian stairs.

• 7. Aftermath and Memory

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  The killing of Sejanus triggered a cascade that lasted for years. Riots broke out; mobs hunted down anyone they could connect to the former prefect. The Senate issued a decree of damnatio memoriae against him: his statues were torn down, his name obliterated from public records and even from coins. On October 24, his eldest son Strabo was arrested and executed. On October 26, Apicata committed suicide, but only after sending Tiberius a letter naming Livilla as an accomplice in Drusus’s poisoning. Livilla’s slaves confirmed this under torture. Livilla herself died, either by suicide or, according to some accounts, starved to death by her own mother Antonia Minor. Sejanus’s younger children, Capito Aelianus and Junilla, were executed in December. Because there was no precedent for executing a virgin, Junilla was raped before her execution.

  Rome’s relief at the fall of Sejanus lasted only briefly. Tiberius then turned on anyone with any connection to Sejanus or who had courted his friendship. The senatorial ranks were purged. Arrests and executions continued under Naevius Sutorius Macro, who took Sejanus’s position as prefect of the Praetorian Guard. The turmoil ran until Tiberius died in AD 37. The historian Edward Togo Salmon later challenged the image of Tiberius as a pure tyrant, writing that across the full twenty-two years of Tiberius’s reign, fewer than fifty-two persons were accused of treason, with almost half escaping conviction. The four innocent people condemned, Salmon argued, fell to the excessive zeal of the Senate rather than to the emperor’s direct will.

  Ancient historians otherwise were nearly uniform in condemning Sejanus. Suetonius Tranquillus took the view that Sejanus was essentially an instrument of Tiberius, deployed to destroy Germanicus’s family and discarded once his usefulness ended. Tacitus attributed much of the decline of Tiberius’s rule after AD 23 to Sejanus’s corrupting influence, though Tacitus is also harsh on Tiberius. The relevant portion of Tacitus’s Annals covering the period of Sejanus’s fall has been lost entirely. Among those caught in the regime’s violence was the historian Aulus Cremutius Cordus, brought to trial by Sejanus in AD 25 for having praised Marcus Junius Brutus and called Gaius Cassius Longinus the last of the true Romans. The Senate ordered his writings burned. Cordus starved himself to death. His daughter Marcia preserved his work so it could be published again under Caligula. Seneca the Younger addressed his letter To Marcia, On Consolation to her, noting that her father had likely incurred Sejanus’s anger for criticizing him over a self-commissioned statue.

• 8. A Name as Political Weapon

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  Ben Jonson was the first to make extensive dramatic use of Sejanus, drawing on Juvenal’s Satire X for passages in his play Sejanus: His Fall, which was understood as a comment on the fall of Robert Devereux, 2nd Earl of Essex, executed for treason just two years earlier. Around the same time, the anonymous Tragedy of Claudius Tiberius Nero, published in 1607, cast Sejanus as a leading figure in a parallel Roman drama.

  In 17th century France, the fall of Cardinal Mazarin was marked in a political pamphlet from 1642, L’Ambitieux ou le portraict d’Aelius Sejanus en la personne du Cardinal Mazarin, drawing a direct parallel between the cardinal and the Roman prefect. In England, George Villiers, 1st Duke of Buckingham, attracted an anonymous manuscript tragedy titled The Emperor’s Favourite. The arrest of Sir John Eliot in 1626 for comparing Buckingham to Sejanus before Parliament showed exactly how volatile the comparison had become.

  After Buckingham’s death in 1628, when the analogy was safer to publish, a translation appeared under the title The Powerful Favourite, the life of Aelius Sejanus. It was followed in 1634 by Sir Thomas Hawkins’ Politicall Observations upon the Fall of Sejanus, translated from the Italian of Giovanni Battista Manzini. Later in the century, Anthony Ashley Cooper, 1st Earl of Shaftesbury, was targeted in a four-page pamphlet titled Sejanus, or The popular favourite, now in his solitude, and sufferings, published in 1681 under the pseudonym Timothy Tory.

  The pattern continued into the 18th century. Robert Walpole was attacked in 1735 in a popular skit called The downfall of Sejanus, attributed to “a masquerader.” In 1769, Jonson’s play was reissued under the title The Favourite, with a sardonic dedication to Lord Bute denying any comparison between his conduct and that of Sejanus.

  In fiction, Sejanus appeared in Robert Graves’ I, Claudius in 1934 and its television adaptation in 1976, where he was portrayed by Patrick Stewart. Graves made Antonia send her letter of accusation to Tiberius through Claudius, after discovering her daughter’s involvement. Because Pontius Pilate was a nominee of Sejanus and implicated in his anti-Jewish policies, Sejanus also found his way into novels about the crucifixion of Jesus Christ, beginning with Miles Gerald Keon’s Dion and the Sibyls in 1866. The most recent detective novel to feature him, James Mace’s Empire Betrayed: The Fall of Sejanus, appeared in 2013, focused on a military colleague named Aulus Nautius Cursor. For nearly two thousand years, writers reaching for an image of a favourite who overreached have returned to the same name.