AMBITION
(14–37)
The story of the Praetorian Guard under Tiberius is largely about the prefect Sejanus and his successor Macro, and the power they wielded as the commanders of several thousand soldiers in Rome. Under Sejanus’ command, all the praetorians were brought into Rome and established in their own fortified compound, the Castra Praetoria. This turned the Guard from being a potential threat to imperial power into an actual one. Sejanus exploited the vulnerability resulting from an emperor withdrawing from public life and delegating much of the everyday running of the Empire to his praetorian prefect. The dangers of an ambitious prefect were now exposed. Sejanus’ fall was followed by the rise of Macro, his successor who, in the interests of securing his future under Tiberius’ successor Caligula, hastened Tiberius’ death, becoming the first praetorian prefect actively to cause the demise of an emperor.
TIBERIUS TOOK CARE NOT to announce the death of Augustus until the latter’s last grandson by Agrippa, Agrippa Postumus, had been killed. He was murdered by soldiers, undoubtedly praetorians, in the form of a centurion and a tribune. According to Tacitus, the instructions sent to the tribune guarding the young man came from Tiberius but with the pretence that they originated with Augustus, ordering Agrippa Postumus be killed on the same day he died.1 Tacitus regarded this as implausible, and took it for granted that Tiberius was behind it. The actual killing was carried out by a centurion who said that he had been ordered to do the deed, something that Tiberius denied had anything to do with him. Tiberius ordered that the senate be informed. This caused an equestrian called Sallustius Crispus great disquiet; he had carried the original instructions to the tribune and was very worried that the truth now might come out. So he warned Livia that these sorts of goings-on in the imperial household needed to be kept quiet and away from the scrutiny of the senate.2 The episode illustrated how the Guard was already liable to be used as a kind of private secret service hit squad, engaging in clandestine activities and subterfuge on behalf of the emperor.
Perhaps the most remarkable fact about the accession of Tiberius was that although the two consuls for the year 14, Sextus Pompeius and Sextus Apuleius, swore allegiance to him first, the next to do so were the prefect of the Praetorian Guard, Lucius Seius Strabo, and the prefect of the corn supply (annona), Caius Turranius. Only then did the senate take its turn. It was a mark of how important the Guard was already becoming or, to look at it another way, it was indicative of the marginalization of the senate in a system where the head of state was now a dynastic emperor, regardless of the constitutional window-dressing. Tacitus acerbically dismissed this as a time when senators and equestrians were ‘plunged into slavery’.3
Tiberius was equipped with the same level of formal powers that Augustus had enjoyed, even if he lacked the same extraordinary level of prestige and auctoritas. This was in spite of the fact that his career as a general and senator placed him at what would have been in any other circumstances a very high level. In 20 BC, when aged only twenty, it had been Tiberius who received the standards lost by Caesar’s then co-triumvir Crassus at the Battle of Carrhae in 53 BC against the Parthians. He had also saved Rome during the Illyrian Revolt of AD 6–9, and led the stabilization of the Rhine frontier after the Varian disaster in AD 9. His military reputation greatly facilitated the transmission of power.
Tiberius’ elevation to the principate was thus more or less automatic, despite the process of succession being unprecedented. It was also extremely difficult, fraught with risk and uncertainty. To his credit, Tiberius made no attempt to match Augustus. Instead he posed as guardian of his stepfather’s name and reputation. Since Augustus had left each praetorian 1,000 sestertii in his will, twice the amount bequeathed to troops in the urban cohorts, and more than three times that set aside for legionaries (300 sestertii), we can easily gauge how important he felt it was to ensure their loyalty was retained.4 The figures maintained the differential with the rest of the army that had been established from the inception of the Guard as a permanent body. The rates correspond surprisingly well with the rates of pay estimated from Tacitus’ account of the grievances felt by legionaries on the frontier about the fact that praetorians were being paid at a ratio of about 3.2:1 compared to them.5 At 3.33:1 the ratio for the bequests in Augustus’ will was similar and was based on the need to use rounded figures as discussed earlier. If the praetorians were to be awarded 1,000 sestertii (250 denarii), matching the amount they may have been paid then thrice annually, then maintaining the same ratio applied to pay would have meant giving legionaries either 312.5 or 333 sestertii each as a bequest. It was obviously much simpler to round this down to 75 denarii (300 sestertii), which is what they were paid every four months. Given that there were far more legionaries than praetorians, the saving was substantial (around 1.5 million sestertii).
With the Guard’s loyalty purchased, Tiberius took no chances. The Guard was instantly mobilized to be with Tiberius wherever he went, accompanying him into the forum or into the senate, in accordance with its primary function. To assert his control of the praetorians Tiberius gave them their new watchword when Augustus died.6 This was probably the moment, if Tacitus’ description of events can be taken at face value, when the Guard first appeared openly as a public display of an emperor’s power. The symbolism of being able to grant a military watchword as a mark of the transition of power was considerable and reflected the inherent nature of the principate, however carefully cloaked it had been in civilian and constitutional guise. Tiberius had good reason to use the praetorians like this. The armies in Illyricum and Germany mutinied when they heard about his accession, the latter resenting that they had not chosen the emperor themselves and preferring their then commander, Germanicus. Interestingly, the mutinying legionaries also demanded the same level of pay enjoyed by the praetorians.7 The mutinies were suppressed but they demonstrated how vulnerable a new emperor could be.
Although Tiberius focused his immediate attention on the funeral obsequies for Augustus, the use of a military guard of forty praetorians at the funeral became a worrying source of possible ridicule; even though Augustus’ takeover of the state had been so comprehensive, apparently he had still felt the need to make provision for military protection in order to ensure his funeral went off peacefully. Tiberius also felt sufficiently insecure that he dared not allow Seius Strabo, the praetorian prefect, to leave Rome to help crush a mutiny in Pannonia.8 This showed a remarkably conscious dependence on the praetorians from the outset and it must have communicated to the Guard how much latent power they might have.
Tiberius, however, had a potentially sound practical reason for placing himself in such an unequivocal position. Although Tiberius had had a very successful military career, his nephew Germanicus, son of his deceased brother Nero Claudius Drusus (d. 9 BC), was not only similarly successful but also extremely popular, especially with the Rhine army, and a good deal younger. In AD 4 Germanicus had been adopted by Tiberius at Augustus’ insistence. This implicitly marginalized Tiberius’ own son, Drusus, from the line of succession. Germanicus was married to Augustus’ granddaughter Agrippina (the Elder), meaning his five children were descended from both Augustus and Livia, a fact enhanced by Agrippina’s inspiring fertility. Drusus was married to his cousin Livilla, sister of Germanicus, daughter of Tiberius’ brother Nero Claudius Drusus and Antonia Minor, herself daughter of Antony and Octavia and therefore Drusus could only claim descent from Livia. Moreover, Drusus’ great-grandfather was an equestrian called Pomponius Atticus, which was something of an embarrassment to the senatorial Claudian family.9 So, in terms of lineage, it was not surprising that Germanicus and his family were favoured by Augustus. Since Tiberius was already fifty-four when he became emperor, it is obvious that Augustus had foreseen the need to set out plans for the succession, especially having already seen Marcellus, Agrippa and his grandsons predecease him.
Shortly after Tiberius’ accession, Seius Strabo’s son Lucius Aelius Sejanus was appointed co-prefect. This particular example of nepotism, both routine and completely accepted in the Roman world, was to have devastating consequences. Within a year Sejanus held the position on his own when his father was promoted to the most senior equestrian post, the prefecture of Egypt, where he probably died in office. This is the first clear example where the inconsistency in the number of prefects becomes obvious. Seius Strabo had held the position on his own before his son joined him. The two men made an impact. After Sejanus’ fall some eighteen years later, an equestrian called Marcus Terentius defended Sejanus’ record to the senate, recalling how impressed he had been by father and son commanding the praetorian cohorts together at this early stage in Sejanus’ career. The senator and historian Dio wrote in the early third century and took a different view. He had access to two centuries of imperial Roman history. With this before him he was able to state unequivocally that, with the single exception of Plautianus under Commodus, no other praetorian prefect had come close to Sejanus in terms of power gained.10
Sejanus had a trusted pedigree as a member of the equestrian order. This must have contributed to the ease with which he inveigled himself into Tiberius’ favour from the moment of his appointment, so much so that the emperor would come to call him socium laborum, ‘my partner in labours’.11 His father had been on the staff of Augustus’ grandson Gaius before rising to the position of prefect of the Guard, which from AD 12 he held jointly with his son. It is hardly surprising that Tiberius, the most reluctant of emperors, fell into Sejanus’ trap, or at least so it seemed.
Sejanus soon had a chance for an outing with part of the Guard. The death of Augustus occasioned a mutiny amongst the Pannonian legions in the Emona (Ljubljana) region in the summer of AD 14. At the time the Pannonian units were under the command of a former consul (AD 10) called Quintus Junius Blaesus, who happened to be Sejanus’ uncle. Blaesus suspended normal military routines in observation of Augustus’ death but the consequent inactivity led the soldiers to listen to a barrack-room troublemaker called Percennius. Percennius had a sharp eye for what were quite legitimate grievances over ludicrously extended periods of service, poor pay compared to the praetorians and deductions for equipment. Blaesus managed to calm the malcontents down and agreed that his son would lead a deputation on their behalf to Tiberius.12 Unfortunately, this only achieved a very brief respite before the mutiny erupted again, this time over Blaesus’ personal troop of gladiators whom he employed to execute soldiers. Before long the chaos led even to the VIII and XV legions planning to fight each other.
When this news reached Tiberius, he sent his son Drusus with two praetorian cohorts and a group of ‘first citizens’ (these included senators who had reached proconsular rank) to find out what was going on and make appropriate decisions on the spot. This is the first attested use of imperial praetorian cohorts ‘in the field’. It is possible that Drusus collected the praetorian cohorts from Aquileia, on the route from Rome to Pannonia. Drusus and the two praetorian cohorts were also accompanied by a unit of praetorian cavalry and the best troops in the German unit, called by Tacitus ‘the guards of the emperor’. Sejanus was sent too, so that he could watch over Drusus; this was a mark of his already conspicuous influence over Tiberius. Dealing with the mutiny proved far from straightforward. Ringleaders openly threatened praetorian soldiers, while the praetorians themselves, along with the legionary centurions, killed soldiers who strayed outside the camp.13 In the end, filthy weather in the winter of 14–15 brought the mutiny grudgingly to an end.
From 15 Sejanus was serving as sole prefect. He was the first of the praetorian prefects to experiment with the power and influence the position enjoyed, and thereby also with the potential power of the Guard as a political force. For the moment, Sejanus’ grand ambitions were not evident, if they even yet existed. Theatres in Rome were becoming more frequently associated with violence. In 15 the violence became worse. In one incident an unnamed tribune of the Guard was injured and a centurion and a number of soldiers, presumably also praetorians, were killed. The senate discussed the problem and decided that praetors could order performers to be whipped. A tribune of the plebs, Decimus Haterius Agrippa, vetoed the proposal as was his privilege, following an earlier decision of Augustus to treat such people as sacrosanct. Haterius Agrippa was related to Germanicus by marriage, so this might have been seen as a sideswipe at Tiberius since the praetorians were by definition his supporters. Gallus’ actions might have led to a split in the imperial family. In fact, no such split occurred, not least because, according to Tacitus, Tiberius regarded Augustus’ decisions as sacred. Nevertheless, it was a significant risk because there was a real possibility that the Guard could have regarded this as a betrayal of mutual loyalty. The Guard was, however, becoming more and more obviously an imperial dynastic protection force, or at least so it appears to us. With so little information about the use of the Guard during Augustus’ reign, one cannot rule out the possibility that practices and usage attested under Tiberius had already been established.14
In 16 the senator Marcus Scribonius Libo Drusus was put on trial, accused of conspiring to start a revolution. An adjournment was agreed so that the investigation could be pursued by interrogating his slaves. Libo was allowed home, but soldiers surrounded his house and disrupted his final dinner party. If the purpose was to spur Libo Drusus on to take his own life, it worked. The soldiers must have been praetorians, here acting as the intimidating and unconstitutional force of the principate.15
Tacitus made much of the idea that there was intense rivalry at the imperial court between the supporters of Drusus and Germanicus. Tiberius undoubtedly promoted his son’s interests, sending Drusus to Illyricum in 17 to improve his military experience. In reality Tiberius also gave Germanicus opportunities to enhance his own popular standing. Soon after Augustus’ death, Germanicus had quashed mutinies in the frontier garrison in Germany. The dangerous situation was primarily defused when Germanicus sent his pregnant wife Agrippina, Augustus’ granddaughter by Agrippa and Julia, and their son Gaius (the future emperor known as ‘Caligula’) away from the volatile legions. The legions concerned were horrified – both mother and son were held in enormous esteem by the soldiers, who liked to think of themselves as their guardians. Chided by Germanicus, the mutiny collapsed in short order, enhancing his prestige even further. The soldiers begged that he would lead them against the German tribes.16
The war commenced with an assault on the Marsi. Germanicus began the war with a nocturnal assault on the tribe after they had enjoyed a festival. With characteristic ruthlessness, the murderous destruction involved killed everyone and anyone his legions encountered over a fifty-mile area. Determined to expiate their mutinous crimes, the legions were easily whipped up by Germanicus in the fighting that followed when other tribes joined in. The following year Germanicus reached the location where Varus and his three legions had been destroyed in AD 9. In 16 Germanicus crossed the Weser and fought the Cherusci at Idisiovisa. At this battle Germanicus advanced with auxiliary units of Gauls and Germans, four legions and two praetorian cohorts. It is likely the two praetorian cohorts had been with him all along.17 In this capacity they were acting as if they had escorted the emperor on campaign – which, with Germanicus as Tiberius’ proxy, to all intents and purposes they had. This single episode is a useful indication of how praetorians could be deployed for military purposes. Since we cannot be certain of the size of praetorian cohorts at this time, these two amounted to either one thousand or two thousand men. Even the upper estimate equates to only 10 per cent of the legionary force of around twenty thousand men. We might also assume therefore that at least seven praetorian cohorts remained in Italy and Rome, but given the piecemeal evidence there is every possibility that some of them had been deployed elsewhere as well.
Despite the violence and the victories, Germanicus’ war in Germany was inconclusive and expensive in terms of Roman losses, so he was recalled. Tacitus believed that Tiberius was simply jealous and sought to frustrate Germanicus, who thought he was within sight of a major success. This was typical of Tacitus’ depiction of Tiberius as a paranoid, jealous and vindictive emperor, but Tiberius may well have had a simple and practical reason. If Germanicus was the principal heir and the war had achieved all it really could, then perhaps the time had come when Germanicus could gain other useful experience and be withdrawn from danger. Tiberius allowed Germanicus the privilege of a triumph in 17.18 Had he and Drusus survived long enough to be rival candidates for the succession after Tiberius, it would have been interesting to see which of them was backed by the Guard. In the event, neither had many more years to live.
Germanicus’ triumph in Rome in 17 advertised and enhanced his prestige, belying the idea that Tiberius had set out to damage his nephew and adopted son. Germanicus was then sent to the east to act as an imperial deputy in the region. Unfortunately, he fell out with the new (and thoroughly corrupt) governor of Syria, Gnaeus Calpurnius Piso. The dislike may have been purely personal but it became impossible for them to work together; Tacitus was content to put all the blame for this on Piso. By 19 Germanicus had come back from a trip to Egypt but fell ill on his return to Syria, believing that Piso was operating black magic against him. According to Tacitus, various clues such as human body parts, spells and curses were found in Germanicus’ room. Germanicus denounced Piso and then died. Piso is reputed to have engaged in an unseemly ‘orgy of celebration’ when the news reached him on the island of Cos. When he subsequently made something of a triumphant arrival in Rome to face retribution, even mooring his ship beside the Mausoleum of Augustus, he provoked popular outrage. Piso, however, committed suicide during his trial when it became clear that Tiberius was not going to support him.19
In the meantime Agrippina headed to Italy with the ashes of Germanicus. She was met at Brundisium by two praetorian cohorts.20 Their presence at this moment symbolized both the significance of Germanicus’ passing and their role as a prestige escort for members of the imperial family. It has never been clear, however, whether any specific criteria were applied when members of the imperial family received praetorian protection.21 The Guard was becoming an integral part of the everyday expression and manifestation of the emperor’s power, status and public image. Accordingly, the praetorians accompanied Agrippina and her husband’s ashes across Italy, the Guard’s officers carrying the urn themselves. With Germanicus dead, Drusus now became the obvious heir, with his own son Tiberius Gemellus (b. 19) next in line. He faced an obstacle in the form of Sejanus.
It was apparent as soon as 21 that Sejanus was a force to be reckoned with. That year a new proconsular governor of Africa was required. One of the candidates was Marcus Aemilius Lepidus, a man with a substantial aristocratic pedigree. The other candidate was Junius Blaesus, Sejanus’ uncle. Aemilius Lepidus offered a number of family and personal reasons why he should be passed over, fully recognizing that Blaesus’ connection to Sejanus made him far more powerful. Blaesus was duly given the job.22
As is the case so often in history, a chance event now helped Sejanus, who had the wit to capitalize on the opportunity. The huge theatre built by Pompey the Great in 55 BC burst into flames in the year 22. The fire was contained, thanks to quick work by Sejanus, and spread no further. Tiberius heaped praise on Sejanus for his assiduous efforts in controlling the conflagration and thereby delivering Rome from what could have been a catastrophe. There is no specific mention that the praetorians were involved in dousing the flames, but it must have been the case that they were, acting feverishly alongside the vigiles either under Sejanus’ orders, or at the very least in his name. Either way he took the credit as men like Sejanus always do. The senate, presumably with an eye to the sort of crawling adulation that might save their own skins, voted that a statue of Sejanus be erected out of gratitude next to the theatre.23 One dissenter to this sycophantic gesture would pay with his life a few years later.
The career of Sejanus now began to expose for the first time how dangerous the commander of the Guard could become. For the moment Tiberius seems to have been wilfully unconcerned. Sejanus made his first significant move the year after the fire at Pompey’s theatre. His ambition in the post was unprecedented, but it was his reorganization of the Guard that turned out to be the most important permanent change, and it would last until the year 312. By 23 Sejanus had installed all the praetorian cohorts in the Castra Praetoria in the north-eastern part of the city. This vast complex, begun in 20 and surrounded by four walls in the manner of a permanent fortress in one of the frontier provinces, transformed the significance of the prefecture of the Guard, ‘up till now of slight importance’.24 It is worth noting that Tacitus specifically says at this point that until this time the praetorian cohorts had been dispersas per urbem, ‘dispersed throughout Rome’. He makes no reference to them being anywhere else in Italy, even though we know this was the case under Augustus. This must mean that the Praetorian Guard had already been brought into Rome in their entirety, perhaps when Tiberius became emperor and made overt use of the praetorians, billeting them in various locations round the city (notwithstanding the fact that some were almost certainly allocated to various ad hoc duties in Italy). If so, the creation of the Castra Praetoria at this point would have seemed more pragmatic and less radical (Plates 3, 4 and 5).
The new base would have resolved at a stroke the everyday problems of organizing the Guard, distributing duties, keeping order and storing equipment. The Castra Praetoria, which would remain a permanent feature until the Guard’s disbandment under Constantine almost three centuries hence, meant also that the ‘soldiers were placed in his [Sejanus’] hands’.25 Sejanus had some very sound practical reasons for this which no doubt assisted in securing Tiberius’ approval for the new installation. It now became possible to maintain reliable discipline throughout the whole Guard and also be confident that any orders reached them all at the same time. Locating them in their own dedicated barracks would also keep them out of trouble in Rome. Of course it also made the Guard a more obvious force, inspiring ‘everybody with fear’, and this would have been most obvious to the praetorians, as it clearly already was to Sejanus.26 This also went some way towards improving the ratio of praetorians to members of the city population and thus the practical prospect of controlling any disturbances.
The move into the Castra Praetoria amounted to the Guard being refounded by Tiberius. This may explain the appearance of the distinctive scorpion emblem that can be seen on some depictions of praetorian shields and standards, along with more routine devices such as lightning bolts. It has been suggested that the scorpion must be connected with Tiberius because it was his birth sign.27 The mostly likely time for the inception of this device then would be the time all the Guard was moved into Rome. The praetorians were around this time joined by some of the men of the Misenum fleet, the Classis Misenensis, also founded by Augustus. Occasionally described as the naval wing of the praetorians, its manpower was largely drawn from the eastern Mediterranean area.28
Sejanus’ ambitions were, for the moment, frustrated by the fact that not only was Drusus alive, but he also inconveniently had a living son in the form of Tiberius Gemellus. Moreover, Drusus bitterly resented the way an upstart in the form of Sejanus was being regarded as the emperor’s ‘partner in labours’. With breathtaking audacity, Sejanus was already having an affair with Livilla, Drusus’ wife. This was a course of action he adopted allegedly as the best means of securing Drusus’ death, by convincing Livilla that her husband’s murder would open the way for the pair of them to seize power. Dio claimed that sleeping with the wives of important men was a key technique Sejanus employed in order to find out what was going on and who was saying what about whom.29 Whether Sejanus genuinely operated to quite that reckless extent matters probably less than the fact that it was clearly believed; certainly it would have helped maximize his perceived power and ability to find out crucial and incriminating information. According to Tacitus, Sejanus was not prepared to leave his future to chance, not least because his indiscreet comments about his ambition were openly talked about by his wife, Apicata.
Sejanus decided therefore to assassinate Drusus, using poison to be administered by a eunuch on his staff called Lygdus. The reason Lygdus obeyed was because Sejanus, apparently covering all possible avenues, had been sleeping with him as well as Livilla, and by these means had beguiled them both into his designs.30 However, we should be careful with such claims. The allegations made about Sejanus’ youthful pimping and sleeping with Lygdus may be true, but they may also fall into the more general ritual of character assassination that ancient historians were so inclined to indulge in. Since Sejanus had turned out to be so thoroughly rotten, corrupt and cynical, he would have been regarded by those historians as a lost cause from the day he was born. Therefore any scurrilous rumour, however obscure, was likely to be gleefully incorporated into a canon of malignant criticism of his malevolence and opportunism.
As the poison took hold, Drusus’ health deteriorated and he died, much to Tiberius’ horror, though at this time the emperor had no idea that foul play might have been involved (if indeed it had been). Such was his trust in Sejanus that he believed the prefect’s story that Drusus had been planning to poison Tiberius.31 Drusus’ death was extremely convenient and it is not therefore surprising that it was believed he had been murdered both at the time and afterwards.32 Sejanus had divorced Apicata in 23 in order to encourage Livilla’s belief that his intentions towards her were sincere and to allay any suspicions that he had an ulterior motive.33
Explaining why Tiberius had fallen so easily under Sejanus’ control is difficult. Tacitus is not particularly helpful here, dismissing Sejanus’ cunning as the principal cause, since it was precisely that which led to his downfall. Tacitus preferred to attribute Sejanus’ rise to the wrath of the gods. His description of Sejanus’ ambition and his assiduous efforts to achieve supreme power makes for a more convincing explanation. If Sejanus was calculating and very convincing, then so was Tiberius vulnerable and very susceptible (or so it appeared). Sejanus also realized that his command of the Praetorian Guard had provided him with the means and status to pursue his intentions. The phrase Tacitus used was magna auctoritate, meaning ‘great influence’ of a kind magnified to the extent that it was almost venerated.34 On the other hand, such was Sejanus’ ambition that it is no less plausible that he was readily exploited by Tiberius, whose disdain for the senators might have stimulated him to use Sejanus as bait. Certainly, given how the story of Sejanus ended, there is circumstantial evidence to suggest that this was what was really going on.
Sejanus had successfully managed to set behind him his youthful career as a pimp in association with Gaius, Augustus’ grandson. That his uncle, Quintus Junius Blaesus, was a friend of Tiberius seems to have helped. While Sejanus clearly had some loathsome characteristics, he must have had sufficient charisma and charm to extricate himself from his disreputable past. One problem Sejanus potentially faced was the simple fact that he was an equestrian. This inevitably excluded him from the high office open to those of senatorial rank, but emperors were prone to be suspicious of ambitious senators and this turned out to be no obstacle to proximity to Tiberius. Tiberius selected a small number of equestrians to form part of his most intimate circle. In addition to Sejanus, another was Curtius Atticus, later killed by Sejanus. Sejanus also had unusual connections. It seems that he had been adopted by the senator Gaius Aelius Gallus, which explains why his name differed from his real father’s.35 Technically, the adoption would have legitimated Sejanus having a senatorial career, but he must have decided that the prefecture of the Guard offered him more real power, and personal access to the emperor. If so, he was right on both counts.
With Drusus dead in 23, the way was open for Sejanus, at least in the short term. Germanicus’ brother Claudius was regarded as totally unsuitable to serve as a successor because of his physical and mental ailments, while Germanicus’ sons, Nero (b. AD 6), Drusus the younger (b. AD 7) and Caligula (b. AD 12), were still too young. It was clear though that before too long the elder two would reach adulthood and present an insurmountable challenge to Sejanus, so long as they lived. There was also the less pressing question of Tiberius’ grandson, Tiberius Gemellus (b. AD 19). All these boys shared one inalienable fact: they were members of the imperial bloodline, which Sejanus obviously was not. Agrippina’s children were descended from Augustus through her mother Julia, Augustus’ daughter. Gemellus was descended from Octavia, Augustus’ sister.
In the meantime, in the summer of 24 the Guard found itself dispatched to deal with the treacherous actions of one of its own former members. Titus Curtisius (or Curtilius) is described by Tacitus as ‘formerly a soldier of the praetorian cohorts’, rather than expressly as a veteran, making it possible that he was dishonourably discharged.36 If this was the case, it would perhaps help explain his actions. Curtisius had started to stir up a slave rebellion, something most free Romans were terrified of because of the rising numbers of slaves. Curtisius led meetings in Brundisium (Brindisi) and then published his manifesto, posting it in public. The rebellion was crushed by the timely intervention of the quaestor Cutius Lupus, who was in the area. He took advantage of a marine force that happened to make port, presumably at Brundisium. When the news reached Tiberius, he sent a praetorian force under a tribune called Staius down to arrest the ringleaders and bring them to Rome.37 Clearly the Guard was also being used to protect the wider public and not just the emperor.
Meanwhile, Agrippina also presented a threat, not least because of the remarkable cachet she had established with the army.38 The hostility between Sejanus and Agrippina and her family worsened, with Tiberius contributing to deteriorating relations.
Sejanus insisted on warning Tiberius of the existence of a partium Agrippinae, ‘Agrippina’s faction’, which needed resisting. The occasion was early in 24 when priests were offering vows for Tiberius’ preservation; they decided to add Nero and Drusus to the vows, apparently in the interests of advertising their loyalty to the imperial house. It turned out to be a bad idea. Tiberius was infuriated that his two great nephews might now develop ideas above their station, but his fury was deliberately cranked up by Sejanus and his talk of the Agrippinian faction.39
The next consequence that year was at Sejanus’ behest, when he decided to prosecute key friends of Germanicus. Their fall would then spread fear amongst other members of the ‘faction’. The first target was Caius Silius, commander of an army in Germany. It was alleged he had wildly bragged that his soldiers had stayed onside while the others mutinied; had his men not stayed loyal, then, so he said, Tiberius would have fallen. His wife, Sosia Galla, was also arrested on the specious grounds that she was friends with Agrippina.40 Silius took his own life and Sosia Galla fled into exile.
Further proscriptions followed and Sejanus’ confidence grew as he realized that being praetorian prefect gave him the power to destroy whomsoever he chose so long as he held the emperor’s unwavering trust. He could also simply obstruct ambitions. The Numidian leader Tacfarinas was defeated by the general Publius Dolabella. Not unnaturally, in return for terminating this protracted war, Dolabella asked for a triumph. He was denied, according to Tacitus, because Sejanus did not want his uncle Blaesus’ glory dented. Blaesus had fought against Tacfarinas in previous years.41
It was starting to look as if the position of prefect of the Guard was, under Sejanus, evolving into an executive post that propelled the incumbent potentially to the heart of imperial rule, with the praetorians themselves being of marginal significance. Part of that impression is down to Tacitus who was far more interested in the relationship between Sejanus and Tiberius. The existence of the praetorians was of course a vital part of that relationship, and so was the fact that all of them were now physically based in one place in Rome from where Sejanus could, at a word, send them anywhere he or Tiberius wanted. Tiberius perceived the praetorians as the physical manifestation of his power in Rome and Sejanus as the medium through which that aspect of his power was operated. Accordingly, Sejanus took care to make sure the power of the Guard was laid out for all to see. His efforts to destroy potential rivals or enemies were experiments in what a praetorian prefect could do, and get away with. Each move he made merely seemed to make another possible.
In 25, not long after the Guard had been brought into Rome in their new camp, Tiberius ordered the praetorians to put on an exhibition of their drill for the benefit of senators. This was apparently with the express purpose of discouraging anyone from considering a conspiracy.42 If that was Tiberius’ intention it must also have made it very clear to the senators just how integral a component of his principate Sejanus was and that making an enemy of him would also mean making an enemy of Tiberius, and vice versa. As it happens, the preceding part of Dio’s accounts lists various individuals who were accused of treasonous crimes in a campaign orchestrated by Sejanus. They included the historian Cremutius Cordus, who was accused of praising Cassius and Brutus and showing insufficient praise for Caesar and Augustus in an account of the civil war and the rise of Augustus. He had even gone so far as to suggest that the tyrannicide Cassius had been ‘the last of the Romans’.43 These were the specious charges laid against him, when in reality he had merely fallen out with Sejanus, whose clients Satrius Secundus and Pinarius Natta prosecuted him. Cordus’ mistake had been, three years earlier, to be the sole voice of criticism when the statue of Sejanus was erected in the Theatre of Pompey after the fire. Cordus had announced, ‘now the theatre is indeed ruined’. Presented with the new charges, Cordus took the opportunity to starve himself to death, succeeding before a plan was initiated to have him force-fed so he could be put to death in a more appropriate way.44
So by the year 25, just over ten years into the reign of Tiberius, to fall out with Sejanus was enough to occasion a death sentence. It was a mark of the sort of place Rome was turning into. Sejanus reached the point that year where his growing confidence led him to overstep the mark. He decided to propose marriage to Livilla, Drusus’ widow, and followed protocol by writing to Tiberius but misjudged the moment. His brazen audacity had gone too far, although it is easy to see why by this stage he thought he could get away with such an outrageous proposition. Sejanus’ oleaginous letter to Tiberius not only emphasized his personal devotion to the duties of a soldier but also how much he valued his connection with Tiberius. Moreover, the marriage would help protect him against Agrippina. It would also of course provide him with an enhanced sense of purpose and fulfilment in the glory of the relationship, given his modest status as an equestrian, which, he claimed, he had no ambition to improve on. Sejanus even pointed out that Augustus had considered marrying Julia to an equestrian.45
It was obvious that Sejanus was trying to integrate himself into the dynasty: by marrying the emperor’s niece he could sire another possible heir to Tiberius. This blatant move exposed his ambitions, regardless of how he dressed up the request. Tiberius’ preference for his grandson Gemellus and the children of Germanicus remained firmly intact. He replied to Sejanus in an equivocal fashion. The most obvious reason he provided for refusing was simply one of status. It was inconceivable that Livilla would be content to spend the rest of her life married to an equestrian.46 The emperor darkly warned Sejanus that senators were already complaining to him that Sejanus’ advancement went way beyond what was appropriate for an equestrian. In the event Tiberius did no more than delay the marriage, which eventually took place in 31, and said that he planned to make him and Sejanus inseparable, but would not disclose (as yet) the means by which he would do that.
Concerned apparently by the revelation that he had enemies in high places, though it is hardly credible that this had not occurred to him already, Sejanus now encouraged Tiberius to withdraw from the centre of government. This appears to have been the point at which he started to contemplate becoming emperor himself, if he had not already done so. Once Tiberius was installed in a suitably remote place, he, Sejanus, would control access to the emperor who would inevitably have to hand over more and more responsibility for ruling to him. That he had several thousand soldiers under his direct command made Sejanus’ plans more than a foolish conceit; he had a very real prospect of seizing power and becoming emperor if a coup was carefully timed.
Sejanus tried to manipulate events but was also helped by circumstance. Agrippina tried to secure general permission to remarry, though no specific candidate seems at the time to have been mooted; Tiberius declined her request anyway. This was scarcely surprising – had she remarried, the inevitable consequence would have been a man brought into the imperial orbit who might have presented a new threat. Sejanus would have been as unhappy about that as Tiberius, but that possibility seemed now to have been removed. In 26 he decided to tell Agrippina that Tiberius was planning to poison her at a banquet. Agrippina spurned the food only for Tiberius to be offended at the thought that he might be planning such a dark deed.47
Sejanus had successfully increased Tiberius and Agrippina’s mutual paranoia. Not long afterwards, Tiberius and Sejanus dined in a seaside grotto near the Villa Spelunca. During the meal a rock fall buried some of the staff, to everyone’s horror. Sejanus leaped to his feet and placed himself on all fours over Tiberius in the manner of a protective canopy. This conveniently created the impression that he was selfless and demonstrably more trustworthy. Meanwhile he continued to work on Agrippina’s family, encouraging allegations to be made about her eldest son Nero while claiming to Nero’s younger brother Drusus that their mother preferred Nero. These suggestions were neatly enhanced by the idea that should Nero be removed then Drusus’ own prospects of becoming emperor would be greatly improved.48
By 27 Sejanus’ dreams had come true. Tiberius had moved to the island of Capri, off the southern tip of the Bay of Naples. Sejanus’ power in Rome was now effectively unchallenged, and even extended effectively to approving candidates for the consulship. Doubtless he exploited his position to use speculatores in the Guard to maintain secure communications between the island and Rome. The potential threat posed to the principate by a sole prefect of the Guard was on the verge of being realized. In 28 an altar was voted by the senate to ‘friendship’ (amicitia); it was set up with statues of Tiberius and Sejanus on either side. We have no knowledge of the feelings of the individual praetorian soldiers at this time, but it is difficult to believe they were unable to bask in some reflected glory as their commander blazed his way across the firmament. The drill display put on some three years earlier must have impressed the participating praetorians as much as it intimidated the senators. Perhaps this was when the praetorian tradition of intimidating the inhabitants of Rome, so memorably recounted by Juvenal the best part of a century later, was established.49
Tiberius certainly had praetorians on hand in Capri, doubtless on the face of it to protect him but also surely ordered by Sejanus to keep him fully informed of any developments. One stole a peacock and was executed on Tiberius’ orders, while another was flogged within an inch of his life simply for clearing brambles in the emperor’s way. Sejanus also allegedly assigned soldiers to Agrippina and Nero, ordered to spy on them and their correspondence, and record their findings in minute detail. These men are not identified as speculatores but it is difficult to believe they were not, since the justification for their presence must surely have been that they were part of the bodyguard for the imperial family. If there had been any restraint on Tiberius and Sejanus it had been the presence of Livia but she died in 29. A letter emerged immediately after her death in which Tiberius, thoroughly convinced by Sejanus of Agrippina and Nero’s malicious intentions, accused the pair of various nebulous misdemeanours. Any further plans to follow the allegations through were thwarted for the moment by popular protests that the letter could not possibly be true.50 But within a short space of time Agrippina and her sons had been neutralized.
Sejanus responded to this setback by aggrandizing himself even more. His birthday, on a senatorial decree, was to be publicly celebrated. Anyone who was anyone recognized the self-preserving utility of supporting Sejanus. The result was that innumerable statues of him were commissioned and set up. Since none of these survives it is impossible to know either what he looked like or whether the accompanying inscriptions made much of his position as prefect of the Guard. His prefecture was looking increasingly nominal. In some respects Sejanus was effectively operating a parallel court. Separate representatives of the senate, the equestrians and the ordinary people were sent to both Tiberius and him.51
It was hard to see where this could lead other than to Sejanus being declared co-emperor or seizing power for himself. In Capri the penny finally dropped, unless the reality was that Tiberius had been giving Sejanus a rope to hang himself with for years. For some time, Agrippina’s youngest son, Caligula, had been resident with Tiberius on Capri. Sejanus’ position was now putting Caligula at risk, quite apart from the danger to Tiberius’ grandson Gemellus. If Caligula was to succeed Tiberius then it was obvious that Sejanus could not be tolerated any longer. Moreover, Caligula was the only eligible living male of the imperial family who could claim descent from Augustus himself, through his grandmother Julia, Augustus’ daughter.
Whatever the truth about Tiberius’ relationship with Sejanus, when he heard reports of the way Sejanus was operating in Rome, he realized that there was a genuine risk of the senate turning against him and declaring Sejanus emperor. He had been wrong-footed by the prefect’s manipulation of Tiberius’ associates such that they kept Sejanus informed about Tiberius’ actions but not vice versa. Some of the senate had received Sejanus’ favours, the rest had been intimidated by him; they all knew that he had a loyal Praetorian Guard.52 The key question at this stage must be whether the Guard was the decisive factor. The prefecture of the Guard had been the route to the top for Sejanus. In some respects he perhaps no longer needed it since he had long exceeded his remit in that capacity. On the other hand, the simple fact of the potential force and that no one, now including even Tiberius, had anything to rival it must have rendered him apparently inviolable.
What happened next was attributed by Dio, who had presumably harvested more contemporaneous accounts, to Tiberius’ dissimulation. If this was the case, then Tiberius showed remarkable presence of mind. If not, we must assume that Tiberius was still so beguiled by his prefect’s attributes that he continued to shower him with favours. We cannot verify the story either way, since the account by our principal source for the period, Tacitus, is missing for part of 29 on into 31. In Dio’s version Tiberius was smart enough to see that he could not thwart Sejanus by openly confronting him. Instead, he elevated Sejanus to the position of consul, though it is not certain if he continued officially to be prefect of the Guard at the same time. Through his adoptive father, Gaius Aelius Gallus, Sejanus was theoretically eligible to become a consul one day, even though he had not held any of the other senatorial magistracies and had remained an equestrian. This was also the time when, according to Dio, Tiberius started calling Sejanus ‘partner in my labours’, though Dio regarded this as another way in which the emperor sought to put Sejanus off his guard. According to Josephus, it was Livilla’s mother, Antonia, who realized what Sejanus was up to and informed Tiberius.53
Naturally enough, the career of Sejanus is not mentioned on Roman imperial coinage. Indeed, there was no reason why it should have been. Such appointments never usually were. Sejanus’ name does, however, appear on a copper as of Tiberius struck at Bilbilis (Augusta Bilbilis) in Spain, a local product in the Roman provincial coinage series. The obverse depicts Tiberius and his titles and on the reverse are the names and titles of the two Roman consuls for the year 31 – the emperor, and Lucius Aelius Sejanus (Plate 6).54
Sejanus’ celebration by Tiberius as his partner was widely accepted as sincere. Since Roman society operated with a system of allegiance and deferential respect in return for protection, Sejanus was awarded the same honours as the emperor. It was agreed that the two would share the consulship every five years and, even more extraordinarily, that Sejanus’ imago would be sacrificed to as part of the imperial cult.55 Meanwhile proscriptions against senators who were suspected of being treasonous proceeded apace. Sejanus apparently had no idea he was to be accused of treason himself, something which conflicts with the accounts of the inside information he had been able to amass. Around the beginning of 31 Sejanus was instructed by Tiberius to go to Rome ahead of him on the grounds that he was ill. This was accompanied by a grand show by Tiberius of what a wrench this parting would be.
Sejanus also seems to have courted popular support amongst the Roman mob. A fragmentary inscription from Rome appears to quote a speech from Tiberius after Sejanus’ fall. It refers explicitly to how ‘Sejanus’ wicked incitement’ had destroyed sixty years of peace after he held ‘evil assemblies on the Aventine when he was made consul’. Tiberius bemoaned the fact that he was reduced to being the companion of a walking stick, a reference to his advanced years, and to being a suppliant.56 The significance is not entirely clear but the Aventine Hill was the traditional setting of the early Republican ‘conflict of the orders’ between the patricians and plebeians. In 494 BC the plebeians seceded from the Republic and withdrew to the Aventine Hill in Rome. The occasion had been mythologized in Roman lore and perhaps Sejanus had sought in some way to challenge the notion of the ruling elite by presenting himself as some sort of popular leader. This is a great deal to read into one inscription, the reading of which is not even certain. What can be inferred from the text suggests it is authentic, but the occasion to which it refers goes completely unmentioned in the extant sources. One of its greatest values is to support the Roman historians’ depiction of Sejanus as someone who had gone far beyond being a mere praetorian prefect. He was in every sense a major and notorious political figure whose career was to echo down the centuries.
Once in Rome, Sejanus and the senate became the bewildered recipients of a series of increasingly bizarre correspondence from Tiberius. Some of the letters offered unctuous praise for the prefect, some denunciations, while others rewarded or punished some of Sejanus’ friends. Sejanus was left thoroughly disorientated but nothing really changed. He was awarded proconsular powers, as any consul would expect to be. Although it is plain that Tacitus and Dio assumed Sejanus planned to become emperor all along, this is difficult to accept without question. Sejanus was clearly a slick operator and he must have been intelligent enough to see that his best option was to act as a protector during the principate of Tiberius Gemellus, the emperor’s grandson, or that of his great-nephew Caligula who now looked as if he was being earmarked as one possible successor. Agrippina and Nero were exiled. Nero then died in early 31, probably either being killed or committing suicide, leaving only Drusus, then in prison for allegedly conspiring against Tiberius, as a potential obstacle. He was also killed in 33.57
Tiberius also started banning any honours that might have to be given to Sejanus as well as himself. This occasioned the perception that Sejanus’ power was beginning to slide. In order to prevent Sejanus realizing the game was up, Tiberius put it about that Sejanus was to be given the tribunician power. This was tantamount to naming him as a successor, just as had happened with Tiberius himself in 6 BC. He had also offered the prefecture of the Guard to Quintus Naevius Cordus Sutorius Macro and given him instructions. Macro had served at some point as prefect of the vigiles, a position that would have brought him to the emperor’s attention, though there is no evidence he held the post in 31.58 Macro entered Rome at night and made contact with one of the two consuls for 31, Memmius Regulus (the other was Tiberius), and the prefect of the vigiles, Graecinius Laco. Critically of course the vigiles were not under Sejanus’ direct control. On the morning of 18 October 31, Macro found Sejanus and told him that he brought news of the tribunician power that was to be awarded him.59 Sejanus fell for it and entered the senate, now assembled in the Temple of Apollo on the Palatine Hill, delighted at this news.60 Outside, Macro instructed the praetorians who had been guarding Sejanus and the senate to return to the camp. He achieved this by the simple expedient of showing them a letter from Tiberius granting him the emperor’s authority. Sejanus was about to be hoist with his own petard. In bringing all the praetorians into Rome, he also made it possible for the loyalty of the entire Guard to be transferred to someone else in one stroke. And indeed it was.
The Guard was kept out of what followed. Under Graecinius Laco’s command, the vigiles surrounded the Temple of Apollo to guard the senate while Macro headed off to the praetorian camp to take control there before the news reached the Guard. Meanwhile, the emperor’s letter was read out in front of the senators and Sejanus, presumably by Memmius Regulus.61 The text is not extant in any form but instead of praising Sejanus and heaping honours on him, the letter simply ran him down little by little with a litany of minor criticisms that led finally to the senate itself denouncing him. Crucially, it had been expected by the whole senate that Sejanus was about to be awarded the tribunician power. When it became apparent that no such privilege was on offer the mood changed. His supporters abandoned him and some senators restrained him from leaving. It took time to establish whether Sejanus had a dangerous support base in the senate. Memmius Regulus was worried that a vote would bring out Sejanus’ supporters. Instead, he asked a single senator whether there was any good reason not to imprison Sejanus. The answer was that there was indeed no reason, so Sejanus was led out to prison by Regulus, along with other senators and Laco (Plate 7).62
Some, perhaps most, of the senators turned on Sejanus like dogs that had smelled blood. He was assaulted by them and by the mob outside who had followed the proceedings. With not a praetorian soldier in sight, the senators assembled in the Temple of Concordia Augusta and condemned Sejanus to death.63 Sejanus was executed and his body cast down the Gemonian Stairs, which led down from the Capitoline Hill to the Roman Forum, a location that could not have been more prominent or public. He was followed shortly afterwards by his children. These included his son Strabo, named after his grandfather.64 Mayhem ensued, with anyone believed to have collaborated with Sejanus being attacked. A few days later, Sejanus’ former wife, Apicata, committed suicide, having told Tiberius that Sejanus had murdered Tiberius’ son Drusus at the behest of Livilla, though this contradicts Tacitus’ suggestion that Livilla had not been in on the plans.65 Sejanus’ remaining children were also put to death, his virgin daughter Junilla apparently being raped by the executioner in order to legitimate the execution of a female. Their bodies were also dumped on the Gemonian Stairs. Other members of Sejanus’ family were hunted down and killed, including his uncle Blaesus.66 Livilla was subsequently either killed by Tiberius or starved to death by her disgusted mother Antonia.67 The killings were a massive act of revenge against Sejanus for coming so close to overturning the system established by Augustus (Plate 8).
As has been demonstrated by Robert Graves in his novel I, Claudius, it is easy enough to depict Sejanus as exclusively focused on supplanting Tiberius in order to become emperor, and Tiberius as calculating and underhand in wrongfooting the ambitious prefect. Such a depiction depends on taking at face value the way both Tacitus and Dio portrayed the two men. In reality, Sejanus’ ambitions may have been less focused and Tiberius’ scheming rather more strategic. It is just as possible that Sejanus’ ambition increased by increments as he felt his way forward and detected what was possible in the light of the latent force he had at his disposal in the form of the Guard. Tiberius’ letter to the senate, although damaging, really acted as a kind of catalyst for a great deal of pent-up resentment, but whether he really expected the outcome that occurred is a moot point. The fall of dictators, and Mussolini is an excellent example, is often accompanied by a cathartic explosion of revenge from followers who feel betrayed, usually as a result of the self-loathing occasioned by realizing they have been fooled. Today, no statue or likeness of Sejanus is known; they were all destroyed in the eruption of damnatio memoriae that followed. The coins struck at Bilbilis in Spain bearing his name were liable to be defaced, with the letters L AELIO SEIANO carefully chiselled off.68 In Rome there was a palpable sense of fear amongst senators who had at least pretended to support Sejanus that they would now be the victims of vengeance. Not surprisingly, some over-compensatory gestures were manufactured in the form of a statue of Liberty to be erected in the forum, an annual festival of horse racing and wild-beast hunts to be held on the day of Sejanus’ death. Awarding honours similar to the ones Sejanus had been awarded was now banned, but in short order they were soon bestowing privileges on Macro. Macro had succeeded Sejanus, presumably as part of his reward, though we do not know for certain that this was the deal. He was even awarded senatorial propraetorian status and the right to wear their toga.69
The Praetorian Guard, meanwhile, now found itself in a potentially very vulnerable position. The praetorians were by definition Sejanus’ men but they were disgusted that the inferior vigiles troops had been treated as if they were more loyal to Tiberius.70 This would have been hugely offensive to their sense of honour, given the oaths they would have taken. Enraged, they started looting Rome. No doubt, however, the favours so swiftly awarded to Macro must have helped assure them that their status was secure. This is a reminder of the difference between the office of the prefect and the praetorians themselves. Sejanus had used the prefecture as a vehicle. His behaviour depended in part on the potential force the praetorians offered; the threat was very real – Tiberius had allegedly been worried that Sejanus would take control of Rome and then sail with a naval force down to Capri to attack him. Had this happened, Macro was under orders to release Drusus from prison and declare him emperor to sidestep Sejanus.71 Tiberius also moved to secure the loyalty of the praetorians, fully aware that despite the support they had shown Sejanus he had no choice but to buy them. He was more suspicious of the duplicitous senators who were now swearing loyalty to him when but a short time before they had been actively fawning around the very man who had betrayed him. Tiberius won the praetorians over with ‘words and money’, a principle that would play a decisive part in imperial events in years to come. Each received 1,000 denarii for staying loyal to him. He also secured a senatorial decree that the praetorians be paid from the public treasury. This was a very useful means of making it appear more credible that the praetorians were public servants rather than the emperor’s personal staff.72
The real issue here is whether the outcome was what Tiberius had planned all along or whether Sejanus had been the driving force until he was rumbled. After all, the whole Sejanus affair had exposed the senators, Cremutius Cordus being one of the very few exceptions, as mealy mouthed, unreliable, self seeking and duplicitous. It is feasible that Tiberius had seen Sejanus for what he was from the outset. Easily tempted to self-aggrandizement, Sejanus was lured into a trap along with most of the senate. Tiberius had all the proof he needed, and with the praetorians secured he had the means to keep the senators under control. The truth lies probably somewhere in between. Sejanus seems, by all accounts, to have been a particularly good example of a nauseatingly greedy, ambitious and cynical opportunist, so it is difficult to believe that he was merely a victim of Tiberius’ dissimulation and cynicism. On the other hand, once Tiberius had the measure of Sejanus, his response showed that he was in every respect Sejanus’ equal, if not even more duplicitous.
After the fall of Sejanus, Macro remained praetorian prefect until he was removed during the first year of Caligula’s reign. Tiberius’ generosity towards the praetorians was short-lived. In 67 BC the Roscian Law had set aside the front fourteen rows of the theatre for the equestrian order. In AD 32 a senator called Junius Gallio proposed that this section of seating be additionally opened to praetorians who had completed their term of service. Tiberius was furious, outraged not only that a senator should deem it fit to interfere with the terms of service for soldiers when that was the prerogative of their commander (that is, himself), but also as this was not something Augustus had suggested.73 Tiberius accused Gallio of being a Sejanus-supporter who had set out to corrupt the simple-minded soldiers by giving them ideas above their station. The incident is primarily interesting for showing that even though the praetorians were under the charge of a prefect, their real source of authority and position remained the emperor. Gallio was forced into exile on Lesbos, which proved too comfortable, and so he was brought back to Rome to be placed under house arrest.
Sejanus still cast a long shadow. Tacitus was disgusted by the hypocritical way in which so many of Sejanus’ former friends denied their association with him. Informers, who in one case at least included a tribune of an urban cohort, were used to bring charges against those guilty of being involved with Sejanus. Only one, an equestrian called Marcus Terentius, was prepared to own up honestly to his relationship with Sejanus, freely admitting that he had been a friend and that he recognized this admission would now do him damage.74 The equestrian body as a whole selected Tiberius’ nephew Claudius (the future emperor) to be their special representative to carry their best wishes to the consuls.75 Nevertheless, before the year was out Tiberius ordered the execution of anyone still in prison who was accused of association with Sejanus. He even went so far as to order the death of his great nephew Drusus, still malingering in prison.76 Agrippina took her own life shortly afterwards, having given up hope that the death of Sejanus would bring about a reversal of her fortunes. Her tombstone, set up in the Mausoleum of Augustus during the reign of her son Caligula, survives and recounts her astonishing career (Plate 9).
Beyond Rome itself other communities asserted their loyalty to Tiberius. To fail to do so might have raised questions, though Sejanus had now become subject to damnatio memoriae – and could not be named. So, at the colony of Interamna Lirenas (near modern Pignataro Interamna) in central Italy an inscription was set up in 32 to the ‘perpetual safety of Augusta and the public liberty of the Roman people’. The text also added a dedication to the foresight (providentia) of Tiberius ‘now that the most deadly enemy of the Roman people [Sejanus] has been removed’.77 It was commissioned by Faustius Titius Liberalis, a local priest of the imperial cult (sevir Augustalis). Such men were usually successful freedmen who had professional connections with the freeborn decurial class. Evidently, Liberalis thought it worth his while to assert his affiliations in the new climate. Further afield, in Gortyn in Crete, an even more cryptic inscription was set up by the proconsular governor Publius Viriasius Naso to the ‘divine majesty and foresight’ of Tiberius, specifically to the ‘foresight of 18 October’, the day Sejanus was toppled.78
Early in 33 Macro first appears in the extant text of Tacitus as prefect of the Guard. He was instructed to escort Tiberius, along with selected tribunes and centurions, on his way to the senate house.79 This is the first description we have of the senior officials of the Guard being deployed in a practical everyday way as part of the emperor’s entourage. Tacitus presents it as a new development. What was not so new was that by 37 Macro seems to have headed some way down the same road as Sejanus. Caligula, the younger brother of Nero and Drusus, and Tiberius’ co-heir with Tiberius’ grandson Tiberius Gemellus, had been married to a woman called Junia Claudia in 33, but she had died in childbirth not long after. Caligula next embarked on an affair with Macro’s wife, Ennia Thrasylla. It is not clear whether Macro instigated this in order to ingratiate himself, or whether Caligula started the affair to beguile Macro into believing that acquiescence in his wife’s infidelity would be to his advantage and that he would therefore help Caligula get rid of Tiberius. Either way, providing his wife to the emperor was a new duty for a praetorian prefect.80 Caligula even went to the extent of promising to marry her if he became emperor. Tiberius was aware of Caligula’s scheming but had a problem: his grandson Gemellus was too young to succeed. Caligula was tainted by association with Germanicus, according to Tacitus, who was convinced that hatred of Germanicus had dictated many of Tiberius’ actions. The only other candidate, Tiberius’ nephew Claudius, was regarded as mentally impaired. Tiberius decided to leave the future to fate, sure that Caligula would succeed him, but appeared to be resigned to the inevitable fact that Caligula would kill Gemellus and then be killed himself.81
Macro was clearly engineering his position for after the death of Tiberius (and was criticized by the emperor for doing so), and secured evidence to facilitate the disposal of his opponents through interrogation of witnesses and the torture of slaves.82 Quite what Macro’s motivation was is unclear. There is no sense, as there was with Sejanus, that he might have planned to take supreme power for himself. Tacitus believed that Macro had been chosen to topple Sejanus because he was even more depraved than the latter.83 Macro seems to have acted in a more conspicuous fashion as the emperor’s personal attendant. He was clearly on hand in March 37 when Tiberius was fading and received personal updates from the emperor’s doctor, Charicles. Tiberius expired on 16 March, or so it was believed, and Caligula prepared to succeed him. Tiberius had, however, only plunged into a temporary bout of unconsciousness, his breathing being so light that it was assumed he had died. He rallied and called for food, causing instant panic. If Tacitus can be believed, Macro ordered Tiberius to be suffocated and everyone else to leave. Dio suggests that Macro actually participated in the smothering as a way of ingratiating himself with Caligula.84
The death of Tiberius thus became, allegedly, the first moment when a praetorian prefect proactively and deliberately influenced the course of history – if, of course, the reports are true. In reality his advanced age made a natural death quite possible, but such a turn of events would not have helped Tacitus or Dio. Since Tiberius was seventy-seven and ill, his death sooner or later was inevitable anyway. In practice, it made no difference: Tiberius was dead and a new age dawned.
The increase in the number of praetorian cohorts to twelve may have happened as early as the reign of Tiberius, or by 47. Typically, the evidence is as confusing as it is enlightening. An inscription, found at Marruvium (Lecce nei Marsi) in Abruzzo in Italy, concerns the career of one man, Aulus Virgius Marsus, who rose from being primus pilus with the III legion Gallica. He appears to have finished his military career by serving in the Guard as tribune of the XI cohort and then the IIII cohort under Augustus and Tiberius.85 The text reads COHORT(IUM) XI ET IIII PRAETORIAR(UM), ‘of the eleventh and fourth cohort of the praetorians’. Since eleven cohorts seems a strange total, and a twelfth praetorian cohort is known to have existed by 65, it is reasonable to suggest that the Tiberian increase involved three additional cohorts, taking the nine cohorts attested in 23 by Tacitus to twelve. If so, the urban cohorts, hitherto numbered X–XII in the same sequence as the praetorian cohorts, would have had to be renumbered initially XIII–XV. There is evidence for this. By 66, for, example there was a XVI urban cohort, reflecting the fact that by 69 the number of urban cohorts had been increased to four.86 However, as is pointed out below, this all relies on the assumption that a regular numbering sequence was in use.
Conversely, it has been suggested that the XI cohort of which Marsus was tribune was in reality one of the urban cohorts, also created by Augustus.87 The inscription was produced in a provincial town at the behest of local magistrates who might only have been dimly aware of the technical difference between the praetorian and urban cohorts which were, by then, all housed in the Castra Praetoria. If so, then Marsus had actually progressed to be tribune of the XI urban cohort and then to tribune of the IIII praetorian cohort. This would have been a natural promotion from an urban cohort to a praetorian cohort reflected in numerous other praetorian tribunate careers recorded on tombstones. Under such circumstances the word praetoriarum on the inscription needs to be interpreted as just generally descriptive of troops ‘of the emperor’s praetorium’, and indicative of a time when specific qualification of the cohort or cohorts concerned had not yet become the standard formula.88 In other words, there remained nine praetorian cohorts for the moment, with Marsus’ XI cohort being an urban cohort. What is not in doubt is that the number of praetorian cohorts was indeed eventually increased to twelve, at least nominally. The evidence of the tombstone of Gaius Gavius Silvanus is relevant here. He died in 65 but at some point in his career he had served as tribune of the XII praetorian cohort, showing that a cohort (or at least one that bore the number XII) was created before that date.89
Just to complicate matters further it has also been suggested that perhaps the Augustan Guard originally consisted of twelve cohorts, with three being subsequently detached to form the urban cohorts, only for three more praetorian cohorts to be created later.90 Although the urban cohorts were paid at half the rate of the praetorians, we do not have any evidence for that differential until the will of Augustus when the praetorians were left 1,000 sestertii and the urban cohorts 500. Certainly there is much evidence to suggest both praetorian and urban cohorts were administered in this way, operated together and were even buried together.91 This means that it is possible the urban cohorts were created out of the praetorians during Augustus’ reign. Whenever it happened, the expansion of the Praetorian Guard must have involved reorganizing the urban cohorts.
As with the praetorian cohorts, it is quite obvious that the system of numbering urban cohorts probably changed on more than one occasion and may or may not have been tied up with the system for the praetorians; it is simply not now possible to identify a single arrangement that explains the disparate evidence we have. All such discussions are generally based on the assumption that a logical and continuous numbering system was used. This was not necessarily the case. Gaps and duplications in the numbering sequence of legions are well known. The numbers XVII, XVIII and XIX were not reused after the disaster of AD 9 in which all three were destroyed. Conversely, in the 70s Britain was home to both II Adiutrix Pia Fidelis and II Augusta, distinguished by their titles rather than their numbers. Similar issues affected the auxiliary forces. Vindolanda seems to have been home at various times to the I, III and VIIII cohorts of Batavians. A II Batavian cohort is attested in Pannonia and Moesia Inferior, but nothing whatever is known of the theoretical IV–VIII cohorts which may well therefore never have existed or, if they did, may have been disbanded before they had time to leave any record. It is therefore entirely possible that for periods in the Guard’s history some cohort numbers were disused or revived as the need arose, making technical discussions about precise numbering sequences futile. Evidence for a XII praetorian cohort does not necessarily mean that twelve active praetorian cohorts were in existence then and continuously thereafter. The Roman army, like much of the Roman world, seems to have been content with systems that were sometimes both illogical and irregular.