69 AD: The Year of Four Emperors

by Gwyn Morgan

  In fact, this arrangement would give Otho the worst of both worlds. Yet, ironically, as Tacitus points out, Suetonius Paulinus and Marius Celsus managed to thwart another of Caecina’s plans, even as Titianus traveled up from Rome. Once again Caecina seized the initiative, from anger that his undertakings had gone badly since the crossing of the Alps and that the fame of his army was fading. Tacitus credits him with four specific reasons. Two were minor, that his auxiliaries had suffered losses in Macer’s raid, and that he had come off worse in skirmishes between the scouting patrols both sides sent out. Two were major, his failure to take Placentia, and the likelihood that Valens would soon arrive with his army. Nothing is said to suggest that Caecina was anxious also to bring the Othonians to battle before they could be reinforced by the Balkan legions. This has been thought odd, especially as the advance detachment from XIII Gemina had turned up by now. But despite their misfortunes Caecina’s scouts must have discovered that the bulk of the Othonian reinforcements were farther away than Valens. It was the imminent arrival of friends, not foes, that spurred Caecina on.

  His plan was simple. Aware that he could not afford to fight a set piece battle after the casualties he had suffered outside Placentia, Caecina decided to stage an ambush on obstructed ground. Much of the Postumian Way lent itself to this, since it ran along a causeway above the surrounding, water-logged plain, and the land was often broken up on both sides into small plots, many of them separated by drainage ditches. Ad Castores, the site of an altar to Castor and Pollux, was especially suitable. It lay about halfway between his base and the Othonian camp at Bedriacum, and here the road was flanked by groves of trees. Caecina left his legionaries behind, partly because they had suffered the heaviest losses at Placentia, partly because an ambush was best entrusted to agile, light-armed troops who could fight in open formation. Taking with him a sizable force of auxiliary infantry and cavalry (neither Tacitus nor Plutarch gives us figures), he positioned the infantrymen in the groves on the sides of the road, under his own command, and ordered the horsemen to move ahead toward Bedriacum. They were to make contact with the Othonians, and by feigning flight to draw them back onto his infantry. If the plan worked, he could inflict heavy casualties on the enemy without taking similar losses himself; he would restore the morale of his troops along with parity, if not superiority, in numbers; and he would regain his reputation for striking successes.

  Tacitus and Plutarch report that Caecina’s plan was betrayed to the enemy, and it has been asserted that he was a fool not to reckon with this possibility, as it doomed his plan. But when he had to induce the enemy to fight at a time and place of his own choosing, did it really matter whether the enemy learnt of his intentions from their scouts or from deserters? The plan was hardly novel; supposedly Romulus had used it once. And it should have required little intelligence in either sense of the word for the Othonians to tumble to his scheme. Yet the Othonians’ response was odd: they assembled every last man they could scrape together, perhaps 13,500 in total. It may look as if they hoped to dispose of Caecina once for all, before Valens could arrive. But the commanding general was Paulinus, and he notoriously refused to run risks. Tacitus terms him “temperamentally a delayer,” and this is not praise. Inspired by the generalship of his own father-in-law, Tacitus had no more patience with overly cautious commanders than he had with rash ones. Paulinus probably mustered all his forces to ensure that nothing went wrong.

  The command of the Othonian cavalry, some four squadrons or 2,000 men, was entrusted to Marius Celsus, and they made contact with the enemy first. It is difficult to reconcile their reported movements with the dispositions with which, according to Tacitus, they went into battle. But Celsus and two of the squadrons seem to have advanced along the road, some distance ahead of the main column of infantry. When they encountered the Vitellian cavalry, the latter put up hardly any fight before turning tail. Then, since Celsus checked his men, the Vitellian auxiliaries broke from cover, attacked the Othonians, and pursued them along the road as they fell back on their own infantry. Caecina would claim later that the auxiliaries had disobeyed his orders, presumably because they should have retreated as soon as Celsus’ reining in his men proved that the ambush was not going to work. But as the Vitellians had been hidden in ambush on obstructed ground, they may have discovered too late that they faced the entire Othonian army. It is hard to fault them for trying to come to grips with the enemy, especially if their own cavalry failed to alert them as it galloped past.

  By rights the Vitellians should have fallen into the kind of trap they had set for the Othonians, but it was not to be. Though Celsus’ cavalry wheeled around them, to take up position in their rear, the Othonian infantrymen were still in column at this stage, and they had to bustle to take up their assigned places on the front and flanks of the enemy. Tacitus states that the Othonian left was made up of a detachment of 2,000 men from XIII Gemina, the first legionaries to arrive from the Balkans, 4 cohorts of auxiliaries, and 500 cavalry. On the right wing, legion I Adiutrix was supported by 2 auxiliary cohorts and 500 cavalry. In the center, on the Postumian Way, 3 praetorian cohorts were deployed in depth, since the causeway was too narrow to allow of anything else. And 1,000 cavalry, a mixture of praetorian and auxiliary squadrons, were held in reserve.

  There were two problems with this. First, Celsus and his two squadrons of cavalry were incapable of shock tactics, and could do little offensively so long as the Vitellian auxiliaries stood their ground. In fact, the Othonian horsemen were unable even to cut the Vitellians off from Cremona. Whenever exactly Caecina began sending for reinforcements, his cohorts had no difficulty in joining him, even though he called them up one at a time. The best Celsus’ horsemen could do was to pin the auxiliaries until their own infantry advanced. Second, Paulinus held the infantry back, refusing to give the signal to advance, until the drainage ditches had been filled up, the ground cleared, and the battle line extended. It may seem hard to believe that Paulinus was put off to find the ground so rough. But he had only just taken up his command, and he need have been no more familiar with the terrain than were the Flavian generals who campaigned here in the fall. Again, if he had no idea how large Caecina’s force was, it was wise to advance on a broad front so as to frustrate the ambush. And finally, he knew that his troops were untrained and untested. That three praetorian cohorts had managed to beat back the assault on Placentia was no guarantee that their peers, let alone the unblooded legion I Adiutrix, would show the same courage in the field. Paulinus could have let them learn to fight by fighting, as Henderson observed, but he ran no risks if he kept them under tight control, left nothing to their initiative, and mounted an attack by the numbers.

  The delay allowed the Vitellian auxiliaries to get off the road and again take refuge on broken ground, presumably to fall back without exposing themselves to Celsus’ cavalry. But, says Tacitus, they sallied onto the roadway a second time, cut down the “the most enthusiastic of the praetorian cavalry, and wounded Gaius Julius Antiochus Epiphanes, prince of Commagene.” This would be readily understandable, if Celsus took all four squadrons of cavalry with him when he wheeled around the enemy rear. If he took only two and, as Tacitus has it, left two in reserve, one praetorian and one auxiliary, the prince probably commanded the latter. In that case, the Vitellians can have wounded him only if this cavalry reserve skirted their own infantry—with or without orders—and acted as a screen for the foot soldiers carrying out Paulinus’ instructions.

  Whatever the case, these Othonian losses persuaded Paulinus to commit his infantry at last, and it looks as if the Vitellian force promptly fell apart. But the rest of Tacitus’ narrative is sketchy. Though he reports that Caecina summoned reinforcements from Cremona a cohort at a time, he does this mainly to secure a transition to the camp, where a mutiny was taking place. The men there were unhappy that they were not being called out en masse, and they blamed Julius Gratus, the prefect of the camp, suspecting him—wrongly—of conspiring with his br
other Julius Fronto, a tribune in the Othonian army.2 In fact, Fronto had already been thrown in chains by his men on the same charge. In any event, Caecina called up his reinforcements piecemeal, and for this too Henderson criticized him harshly, and perhaps rightly. Yet Caecina’s aim was clearly not to prolong the fighting, but to break away, to feed in enough men to rescue those in the trap without allowing the engagement to develop into a full-fledged battle. The arrival of these cohorts added to the confusion, however. The fresh troops were nowhere strong enough to make a stand, and all the men were swept away once panic took hold. Yet the Vitellian losses cannot have been heavy. Though Tacitus gives no figures, he ends his account with the claim that “the setback did not so much frighten the Vitellians as teach them the value of discipline.” Then too, Paulinus sounded the retreat as soon as the enemy line broke.

  Paulinus’ decision gave rise at once to bitter arguments whether “Caecina and his entire army” could have been annihilated. Plutarch holds that it could, Tacitus that it could not. The explanation for Plutarch’s view is straightforward. Since he omitted Macer’s raid, he used this uproar to account for Paulinus’ supersession by Titianus and Proculus. In reality, however, the debate centered on the meaning of the phrase “Caecina and his entire army.” Plutarch took this to denote the Vitellian force in the field at Ad Castores, men who could have been wiped out, if Paulinus had acted boldly. Tacitus recasts the question. For him “Caecina and his entire army” covers the troops in the field and the legionaries left behind at Cremona. On this view, Paulinus made the right decision. Though his infantry were still relatively fresh when he sounded the retreat, he could legitimately wonder whether they possessed the stamina for a 12-mile march, let alone for fighting a second battle at the end of it. Neither Paulinus nor his men were aware of the mutiny in the Vitellian camp, of course. But what the general knew was that if anything went wrong in the pursuit or in the attack on the camp, he would lose control of his men, and that was courting disaster.

  The more interesting question is why Tacitus chose to defend Paulinus, and for this too there is more than one possible answer. Since Paulinus had to justify his conduct of the battle repeatedly, for example, he may have been the first to exploit the ambiguity inherent in the phrase “Caecina and his entire army,” and Tacitus could have followed his lead unwittingly. But as Tacitus attributes a similar rhetorical trick to the general during the council of war before Bedriacum, it is more likely that he seized on this ambiguity for his own purposes. Tacitus was still preoccupied with the issues of trust and loyalty aired in his account of Macer’s raid at this stage in his narrative, and his reading of Paulinus convinced him that the man was loyal. It followed that, however inept his generalship, he must have been doing his best to win the engagement, and so merited the best defense Tacitus could make. As every Roman advocate knew, the best tactic was to sweep the lesser charge under the rug, especially if it was unanswerable (as it was in this case), and to substitute—or to follow Paulinus in substituting—a more serious charge against which a plausible defense could be offered.

  Caecina blamed his defeat on his men, “readier to mutiny than to fight.” But according to Tacitus, the setback also induced Valens’ men to put aside their contempt for the enemy and to show more discipline—as well they might, after a mutiny and a near mutiny during the march from Lucus to Ticinum (Pavia). The mutiny proper was caused ultimately by the eight Batavian cohorts Valens had added to his column. Their boasting about their prowess not only infuriated the legionaries to the point where insults and fist fights were a daily occurrence, but even induced Valens to suspect that the Batavians were trying to sabotage his march. So when, seemingly at Augusta Taurinorum (Turin) around the end of March, Valens was informed of the defeat of the auxiliary forces sent to counter Otho’s maritime expedition, he seized what he thought a perfect opportunity to reduce the friction by sending some of these cohorts to deal with the raiders. The plan backfired. With one of those lightning-swift mood changes to which the troops were supposedly liable (in this instance, no doubt, one encouraged by the Batavians), the rest of his men concluded that he was trying to rid himself of the bravest and most experienced units in his force. When Valens attempted to assert his authority, the soldiery stoned him, and chased him off. He escaped by disguising himself as a slave and hiding in the quarters of one of his cavalry commanders. Meanwhile the men beguiled themselves with the idea that he had pocketed huge sums of money from the people of Vienna that should rightfully have been theirs, then plundered his baggage, searched his tent, and even probed the ground beneath with spears and lances in case he had buried the loot.

  This mutiny was brought to an end by the ingenuity of Alfenus Varus, the prefect of the camp (Valens’ second-in-command on the administrative side). The disturbance naturally lost momentum when the troops found no treasure, and Varus decided to throw them off balance altogether by depriving them of the normal structure of their existence. He ordered the centurions not to make their rounds and the trumpeter not to sound the watches. This disoriented the men so much, says Tacitus, that eventually they stopped whatever they were doing and stared at one another in stupefaction. Lacking a leader, they finally begged for pardon, and Valens made his reappearance, dirty, disheveled, and still in slave’s clothing, but also unharmed. Hoisting him onto their shoulders, the men carried him to the tribunal in delight, and conscious of the realities, Valens reprimanded a few but demanded the punishment of none.

  The column was making camp at Ticinum (Pavia), some 95 miles further on, when the news of Ad Castores arrived, probably around the end of the first week in April. This provoked the near mutiny. Claiming that Valens’ trickery and foot-dragging had robbed them of any chance to participate in the battle, the men refused to wait for orders, set off on a forced march of between 50 and 55 miles, and joined up with Caecina probably in less than 48 hours. It was not a joyous reunion. Caecina’s men took care not to find fault with Valens’ troops, but they shifted the blame their general had laid on them onto Valens’ shoulders, and complained bitterly that he had left them in the lurch. Because Valens’ troops were also attempting to shift the blame away from their conduct, they sided with the younger commander as well. Valens neither relished nor forgave this. With about twice as many troops as Caecina, he thought that he merited proportionately more respect. But the men still preferred Caecina, and there was a slanging match in which Caecina abused Valens as “a dirty old man” and Valens called Caecina “a pompous idiot.”

  Yet once the two men had relieved their pent-up feelings, they put aside their enmity for the time being, and began preparing for the one decisive battle that would win the war. Tacitus puts it a little differently: Caecina and Valens sat back and waited for the Othonians to make the next mistake. This is inaccurate, in that Caecina would set his men to constructing a pontoon bridge. But as this was to be a feint, Tacitus is basically right. And he expresses himself this way because it enables him to make a smooth transition to the Othonians. They were about to make a fatal mistake, as a result of Otho’s decision to come up from Brixellum to Bedriacum and to preside over a council of war.

  At this meeting the Othonians reached two decisions, that they would give battle immediately, and that Otho personally would not take part. Since this led to their defeat and to Otho’s suicide, it is essential to form a clear picture of the purpose of this meeting, the reasoning behind the views expressed, and the effects produced. This is not easy. Plutarch and Tacitus give us accounts of what happened but, as usual, they disagree on some points, and they embed those on which they agree in different interpretations. It would be simple to blame Tacitus for the confusion. He identifies and focuses on the key issues, but he handles them in elliptical fashion. Plutarch’s version is more straightforward, and has often been thought more plausible. But he compresses the material, to keep the focus on his vision of Otho, and he ignores or misunderstands key points.

  To begin with a fact that tends to get lost in
all the discussion, everyone present took it for granted that they had to fight. The Othonians had marched north to do battle with the Vitellians, and all assumed that this one engagement would end the war. The question was timing, whether to fight now or later. Between the meeting and the Othonians’ defeat, however, there would be incidents suggesting that more devious motives were involved, and after the defeat the arguments for delay became inextricably entangled with suspicions that their advocates had been trying to reach an accommodation with the enemy. Plutarch retrojected all this into the meeting, to support one of his explanations for Otho’s decision to fight at once. In so doing, he not only misrepresented the emperor’s character, but also based his account on a misinterpretation of the military situation. As Tacitus saw, the foundations for these conspiratorial views were laid only after the meeting ended.

  According to Plutarch, Salvius Titianus led off the discussion, as the nominal commander in chief. He offered two arguments for giving battle forthwith. The praetorians were elated by their recent success at Ad Castores, and it would be folly not to take advantage of their high morale. And the Othonian troops would lose their enthusiasm and their edge if made to wait “until Vitellius arrived in person from Gaul.” Tacitus, on the other hand, characterizes Titianus and Proculus later as “the men responsible for the worse plan,” but he puts no specific arguments into their mouths. Instead, he launches into the counterarguments for delay, and he has been denounced for abdicating his responsibilities as an historian. This is absurd. When the obvious course was to fight at once, what needed comment and elaboration was the less orthodox plan, to delay.