At the Castra Praetoria Julius Martialis was the tribune serving as officer of the day. Whatever his understanding of the situation when the news reached him, Martialis decided to go along with the plot and was joined by the other tribunes and centurions. It was a remarkable feat, achieved more by force of circumstance and opportunism than anything else. There is no suggestion that the praetorians as a body were about to go over at that moment, even if they had been carefully groomed by Onomastus and his team in the preceding months. It appears also that they did not even know at that point who was seizing power. Eventually the news arrived that Otho was on his way.
There was a serious problem. Galba had with him on the Palatine the duty cohort of praetorians, dressed as normal for them while on that detail in togas, and thus (incidentally) clearly not ready for fighting. It was essential to find out whether they would join the coup or not. Licinianus Piso, Galba’s adoptive heir, addressed the praetorian cohort on the emperor’s behalf. He talked up the challenges faced by Galba, embarked on a character assassination of Otho, appealed to them not to fall in with a conspiracy led by so few men, and inevitably offered a bounty. The speculatores amongst them seem to have disappeared at this point, presumably to join Otho, while the others prepared for action against the rebels by sounding out other military units in Rome. The problem was the rest of the praetorians. Three tribunes were sent to the Castra Praetoria to find out how the land lay. They were not welcomed. Cetrius Severus and Subrius Dexter were threatened, and Pomponius Longinus, notorious for his personal friendship with Galba, was attacked and arrested. The praetorians were joined by the navy, some of whose number had been killed by Galba when he arrived in Rome and others sent back to rowing on galleys, while other units remained uncommitted.
Events moved extremely fast – too fast for Galba and his advisers, though they recognized that once Otho had secured the support of the praetorians and also taken control of the forum and Capitoline Hill then all would be lost. Nevertheless, there was indecision about whether Galba should go and try and take control of the praetorian camp. Extraordinarily, for a brief moment the crisis seemed to be over. A spurious rumour erupted that Otho, incredibly, had been killed by the praetorians in the Castra Praetoria. Loyalists, including the mob and even senators, dropped their guard and burst into the palace. Galba was confronted by a praetorian called Julius Atticus who claimed to have killed Otho. Ever a stickler for protocol, the aged emperor, who might reasonably have been delighted by the news, demanded that the soldier tell him on whose authority he had done this.
The rumours of Otho’s death had been greatly exaggerated. How the story emerged that he had been killed is unknown but can probably be put down simply to the chaotic circumstances and an element of wishful thinking. It seems to have been the ordinary praetorians who really took charge. They placed Otho on a pedestal, brought any soldier who came over to them to Otho to swear allegiance, and warned off the tribunes and centurions, whose loyalty to the coup they doubted. Otho spoke at length to the praetorians and other soldiers, running down Galba’s regime for its corruption and arbitrary executions and explaining that there was no turning back now for the coup. The armoury was thrown open and arms and equipment distributed indiscriminately, regardless of whether the soldiers were praetorians or others. They now faced an armed mob of Galba’s supporters. A rebel force, including the cavalry, evidently left the Castra Praetoria and made for the forum. As they approached, Atilius Vergilio, one of the standard-bearers with Galba’s cohort, ripped off Galba’s likeness from the standard, indicating that they had gone over to Otho. The mob fled. Galba was thrown from his chair and brutally murdered beside the Lake of Curtius in the forum by soldiers of unknown identity. At less than seven months, Galba’s tenure was the shortest principate to date. Within a year that record had been broken twice.
The praetorians had not all gone over to Otho. A praetorian centurion called Sempronius Densus stood fast so that Licinianus Piso could escape. Piso fled down through the forum and took sanctuary in the Temple of Vesta. One of the soldiers who hauled him out and killed him was a speculator called Statius Murcus. Meanwhile, the senators and the mob fled to the Castra Praetoria, falling over themselves to swear allegiance to Otho. The Praetorian Guard had played a major role in toppling a short-lived emperor. Had Galba secured their support from the outset then he may have lived long enough to ensure that Licinianus Piso succeeded him and change the course of history. The Guard had now tasted power in an unprecedented way. The Castra Praetoria had become the epicentre of a watershed moment in Roman history, and the praetorians knew it. The soldiers appointed their own praetorian prefects, Plotius Firmus and Licinius Proculus, Laco being murdered to make way for them. The soldiers also chose for prefect of Rome one Flavius Sabinus, brother of the senator and general Titus Flavius Vespasianus who was even now waiting in the wings for his own chance to become emperor. It was not all ominous. Otho did away with the corrupt practice of soldiers paying centurions for time off, but avoided alienating the centurions. They now received a payment direct from the state for each soldier awarded leave.
The fall of Galba left Rome shaken. The forum was strewn with dead bodies. Worse, news arrived that Aulus Vitellius, governor and therefore commander of the army in the province of Germania Inferior, had led a mutiny, egged on by some of his legionary commanders, Alienus Caecina and Fabius Valens. The crucial day had been 1 January 69 when the legions were supposed to renew their allegiance to the emperor. Many of the soldiers declined, and some openly attacked Galba’s image and name. In the next few days they were joined by armies in other north-western provinces, including Britain and Gaul, all declaring for Vitellius. Vitellius had been appointed to the governorship by Galba, and Tacitus ruminated on how fate had decided that the future of the Empire was to be determined by two of the most repellent men available. The only hope lay with Vespasian, then commanding an army in the east. But it made no difference to the fact that the only prospect seemed to be civil wars like those of a century earlier.
In Rome, Otho responded to the news by trying to step up to the mark of what was required of an emperor. He pardoned one of his opponents, the consul-designate Marius Celsus, but also took the decision to order the death of Tigellinus, Nero’s deposed praetorian prefect who so far had escaped retribution thanks to Galba’s protection. Tigellinus was ordered to commit suicide, which he did after hesitating, using a razor to slit his own throat. He had lived badly, but in Roman terms he died well.
Otho tried to negotiate with Vitellius, offering him the money and opportunity to lead a quiet life. The gesture was reciprocated but the correspondence soon degenerated into mutual abuse, with each even sending assassins to his rival’s headquarters. Otho then ordered a senatorial deputation to go and try and win over part of Vitellius’ army. They were given an escort of praetorians. The diplomatic venture went completely wrong. The senatorial envoys threw in their lot with Vitellius and the praetorians raced back to Rome, armed with a letter given them by Fabius Valens, addressed to the praetorian and urban cohorts. The letter was strangely ambivalent. On one hand Fabius argued that the Vitellian forces were so large that the praetorians and urban cohorts should come over. On the other he castigated them for making Otho emperor when Vitellius had already been declared emperor in Germany. Of course, Otho enjoyed a crucial advantage. He held Rome and was in control of affairs of state at the hub of the Empire with the praetorians as his sponsors. Vitellius was on the periphery and he had no choice but to march on the city. Otho’s grip on Rome was not absolute. The ‘XVII cohort’, probably one of the urban cohorts, was ordered by Otho to relocate from Ostia to Rome. When they arrived, a praetorian tribune called Varius Crispinus was detailed to issue the arriving troops with arms. Crispinus decided to do this after dark because the barracks would be quieter. The armoury was duly opened but the time chosen merely led some of the rest of the praetorians, including some drunks, to assume that Crispinus was organizing a coup. The soldiers convinced themselves they had chanced on a plot by the tribunes and centurions to murder Otho, so they threw themselves into the melee, helping themselves to equipment and cutting down some of their officers before hurtling off to the palace to find Otho.
Otho was hosting a banquet. His guests were terrified but tried to stay calm while they worked out what was going on. Otho told his praetorian prefects, Plotius Firmus and Licinius Proculus, to calm the soldiers down who were now busily cursing the centurions and tribunes and threatening the senate. Otho then advised guests to leave the dining room, a decision that occasioned a mass panic as they exited. Meanwhile the enraged praetorians burst in and demanded to see Otho. In the chaos, Otho panicked too and resorted to pleading with the soldiers. This worked, but not well. The praetorians returned to the Castra Praetoria feeling frustrated, resentful and guilty. The following day the sullen soldiers were told off by their praetorian prefects, but any ill feelings were swiftly mollified by the granting of a donative of 5,000 sestertii to each. Otho then spoke to the men himself. The tribunes and centurions offered to retire in return for their lives and the regular praetorians went back to work after insisting that the ringleaders be executed.
It was twenty-eight years since the Guard had brought Claudius to power, which meant every one of the praetorians was a member of an organization that knew what it could do. Since Otho had become emperor, he knew he had to keep the praetorians both on side and under control. It was a very difficult proposition. He decided to attribute recent events to misguided loyalty on the part of the Guard and hope that by flattering their vanity they would be more inclined to accept that they needed to obey orders without question, and not act unilaterally. They were certainly not to take it upon themselves to threaten the senate, whose support was what legitimized Otho’s regime.
Precisely two praetorians were punished and an illusion of calm followed. The others remained apprehensive and suspicious. Claudius had passed a law banning praetorians and other soldiers from waiting on senators as their clients. This seems to have been overturned now by praetorians who, posing as civilians, infiltrated the houses of aristocrats in order to find out if the families concerned were Vitellian sympathizers. Otho’s coin issues were limited to gold and silver, ideal for paying troops. They depicted some of the usual imperial personifications, virtues and aspirations. One type, unique to his reign, depicted a Victory with the legend VICTORIA OTHONIS, ‘Othonian Victory’; it was clearly designed to promote confidence that his forces would prevail over Vitellius.
The prospect of Vitellius’ advance added to Otho’s problems, which now involved tackling natural disasters including major floods. These caused bridges in Rome to collapse, tenement blocks to be undermined, and a famine. Otho decided to make a move by using his loyal naval force to invade Gallia Narbonensis, since all the land routes were blocked by Vitellian forces. A force would lead the way under the overall command of the praetorian prefect, Licinius Proculus. This seems to have involved five praetorian cohorts, plus cavalry and, even more remarkably, two thousand gladiators, as well as the I legion. Proculus had no experience of campaigns, and so was accompanied by three senatorial generals who included Suetonius Paulinus, who had defeated the Boudican hordes in Britain almost a decade earlier. Tacitus, with predictable senatorial venom, accused Proculus of slating his far more experienced assistants in order to remain in charge. The use of praetorian and urban cohorts in such a prominent position in warfare was a worrying sign of the times and reflected the enormous impact on the Roman world of the growing crisis. That one of Galba’s coin issues in the summer of 68 had been a widely circulated dupondius with PAX AUGUSTA (‘Augustan Peace’), and Otho’s gold and silver types included one with PAX ORBIS TERRARUM (‘peace of all the lands of the world’), must have seemed cruelly ironic.
In the middle of March 69 Otho handed over civil government to the senate, his own duties to his brother Salvius Titianus, and prepared to leave for the war. There was no time to be lost. Vitellian forces were advancing over the Alps. Otho headed out to join the army of five legions and the praetorian contingent of five cohorts. He brought with him what Tacitus describes as the rest of the Praetorian Guard, praetorian veterans (presumably evocati, thereby serving as a solid body of experienced troops), and a ‘large number’ of naval troops. The praetorians first saw action during Otho’s invasion of the Ligurian coast, securing the territory between the inland hills and the sea, while the legions and auxiliaries bore the brunt of the fighting. The outcome was inconclusive and Vitellian forces were already making their way into Italy. Three praetorian cohorts had been assigned to Vestricius Spurinna who was holding Placentia (Piacenza) for Otho, along with a detachment of a thousand legionaries and some cavalry. Recognizing that his force lacked experience and would have been hopelessly outclassed by seasoned troops, Spurinna decided to keep the men safely behind the city’s fortifications. They ignored him out of sheer terror that Vitellian forces under Caecina were on their way. They left Placentia and Spurinna had no choice but to go with his men. The soldiers headed west and after 17 miles (27 km) reached the Po where they decided to make a camp for the night. Creating an overnight base was routine for Roman military forces, but for the effete praetorians the task proved impossibly onerous and demoralizing. Finally, the centurions and tribunes managed to persuade the men that Spurinna had been right all along and back they went to Placentia. The incident is a fascinating vignette of the real quality of praetorian soldiers whose comfortable life in Rome, for all their posturing and political interference, had really left them little more use than weekend military poseurs. On the face of it, these louche Hectors lacked the discipline, coordination and even basic physical ability to function as soldiers in a war setting. This was not a problem peculiar to praetorians; legionaries stationed in the comfortable setting of a peaceful province could easily lapse into indolence and incompetence as Corbulo had found in Syria in 58.
In spite of this, the prestige of Rome and the praetorian cohorts with the Othonian army became part of the morale-boosting preamble to the two-day fight that followed when Caecina and his Vitellian force arrived. The Vitellians, for their part, dismissed the defenders as circus fans and theatregoers, an allegation that probably had a great deal of truth in it. In the event, the praetorians, for all their apparent lack of moral fibre, turned out to be more than equal to the occasion. They defended Placentia bravely, even hurling millstones down the ramparts on to the attackers to great effect. Caecina was forced to withdraw towards Bedriacum (Calvatone, near Cremona).