charged. Quickly, they drew ahead of their infantry. The Roman alae moved to a trot then a canter.
On both wings, the cavalry clashed roughly level with the stationary line of Roman infantry. In a moment, the combatants were intermingled. All order vanished. Squadrons, smaller groups, even individuals charged, wheeled, retreated, then charged again. In both melees hand-to-hand and distance fighting coexisted. Each mounted man sought to press home his attack or seek safety as his courage or circumstance dictated. On the left, Gallienus caught a glimpse of Gaius Acilius Glabrio. The young senator, resplendent in scarlet and gold, was laying about him manfully. Soon, most such details were hidden by plumes of thick dust.
The Alamanni foot were closing. A number of warriors were falling to arrows. A few were still snatched backwards by artillery bolts. The Roman archers and ballistarii were doing their best. They could not stop the charge. A few parts of the German line seemed to hang back, but the wedges headed by the war-leaders and their household warriors were moving fast. Long hair flying, these big, well-armed men were a fearsome sight.
The barritus had dropped to a low murmur. After their long advance, the Alamanni needed their breath. Stationary, the Romans continued to bellow out their war cries.
Gallienus peered through the dust at the cavalry melees. On the left, Acilius Glabrio and Theodotus seemed to be holding their own. At least the swirling dust cloud had not moved appreciably. The right was a different story. The troopers under Aurelian and Claudius appeared unusually reluctant to stay at close quarters. They were giving ground, being driven back behind the Roman infantry line. Gallienus was pleased.
Javelins flew from both sides, just as the infantry of the Alamanni centre and right reached the caltrops. Running close together, pushed on by those behind, some Germans could not avoid the terrible spikes. Others were too distracted by the incoming missiles to notice the menace underfoot until they felt the searing pain. Warriors fell, shrieking. Battle-mad, their comrades ran over them.
The Alamanni crashed into the Roman line. The din hit Gallienus like a blow. There was one huge noise, louder than a temple collapsing, composed of a myriad smaller noises: shield on shield, steel on wood, men shouting, men screaming.
The momentum of the boars' snouts was driving them into the Roman line. Blades and spearheads flashed. Arrows whistled overhead. Men jabbed, hacked, pushed, shouted. Sharp steel bit into flesh. Men fell. The ground ran slippery with blood and spilt intestines. Men lost their footing. They were trampled in the horror by friend and foe alike.
The Roman line looked painfully thin. At the rear, junior officers shouted, threatened, cajoled. They physically pushed men back into line. They beat men with the flats of their swords, yelling for them to give their all.
From somewhere — disciplina? The hand of a god? Hercules himself? — the Romans found the strength to resist. Digging their heels in the ground, bending their knees, calling out to each other, they pushed their shields into the backs of those in front. The line held. The German wedges were halted.
Except for one out on the Roman right, where there had been no caltrops. Tipped by a gigantic warrior, his sword slicing intricate patterns, the one boar's snout edged forward.
Gallienus snapped orders. One unit of his cavalry reserve cantered forward. The men dismounted. Leaving one in five to hold the horses, the armoured troopers added their weight to the threatened point. Four hundred fresh men made the difference. Here too the line held. For the moment.
Blinking from the dust, Gallienus took stock. The cavalry on the left were still holding out but, on the right, the Romans were losing ground fast. A clear gap had opened between this cavalry action and the infantry combat. The feigned retreat had worked. It was time.
There were only fifteen hundred horsemen still in his reserve. Gallienus was not worried. His plan was working. It was time.
Gallienus unsheathed his sword. His palm was wet. His heart was pounding. It was not fear. There was nothing to fear. The god was with him. Like Antony long ago in Alexandria, he would know if Hercules left him. The emperor signalled the advance.
They set off at a walk. With disciplined ease, they changed formation on the move. What emerged would have impressed anyone. Two solid wedges of armoured men on armoured horses. The smaller, some five hundred men, was led by Aureolus, and rode under the red Pegasus on white banner of the Horse Guards. The larger, some thousand men, followed the imperial purple draco. At their apex was the emperor himself.
Without waiting for an order from the emperor, Aureolus angled his horsemen towards the cavalry melee on the right wing. Gallienus approved. The protectores should show initiative, and none more so than the protector appointed Prefect of Cavalry. The emperor watched as Aureolus quickened the pace. The big horses went from a trot to a gentle canter. They moved easily, making little of the weight of man and armour on their backs. A noble cloud of dust rose behind them.
Gallienus led his men towards the gap between the central infantry fight and the mounted one on the right. He kept to a slow walk, fighting down an urge to hurry. He needed to keep his troop together.
A previously unseen ditch appeared in front of Gallienus. Manoeuvring on a battlefield, there was always something. A ditch, a line of vines, a dry-stone wall — an unexpected obstacle always appeared.
The ditch was not too deep, its bottom dry. Gallienus leant back, letting his mount pick its way down, then forward as they climbed out. A few paces across on the far bank, he pulled up, giving the men behind him a chance to sort themselves out.
Gallienus looked to his right. The Pegasus banner streaming above them, Aureolus's troopers were forging into the confused melee. The men under Claudius and Aurelian seemed to have taken heart and were also pressing the enemy. One or two of the Alamanni had had enough. They were spurring their mounts away south across the plain. On that part of the battlefield the tide had turned.
To Gallienus's left, things were not going so well. In the manmade gloom, the thin, thin line of Roman infantry was being forced back. In places it had buckled dangerously. It could not be long before it broke. Now there was no time to lose, no time to fuss over parade-ground cohesion.
Gallienus kicked on, quickly coming to a near flat-out gallop. His men followed. The hooves of a thousand horses rattled on the hard ground as they surged past the cavalry fight on their right. Gallienus led them in a sweeping curve to the left that brought them to about two hundred paces behind the left rear of the German foot.
Now! Strike now! I am with you. The god whispered urgently in Gallienus's heart. No! Not yet. Not like this. Not with the troopers strung out like the trail of a meteor. Hercules had always been hasty. Too hasty when he had sacked sacred Delphi. Too hasty when he had hurled his guest Iphitus to his death from the highest tower in Tiryns. Gallienus, the emperor, who suspected that, one day, he would be a god, stood up to the god who had once been mortal. There was only one throw of the dice. This charge had to break the heart of the enemy, had to rout their infantry beyond recall. Gallienus could feel Hercules' barely suppressed anger, but also his acquiescence. The god still held his hands over the emperor.
Gently, Gallienus brought his mount to a standstill. Horses snorting and stamping, weapons and armour ringing, officers shouting, the troop reined in and got itself back into order.
The warriors in the rear ranks of the Alamanni infantry were more than aware of Gallienus's men. They looked over their shoulders, pointed, gesticulated. Some turned to face the new threat. Others shouted to their war-leaders. If any of the latter heard, caught up in the business of staying alive at the front of the fight, there was nothing they could do.
'Now!' Gallienus spoke as much to his god as to the men behind him. The bucinatores blew the charge. The brassy notes sliced through the din of battle. The now close-ordered arrowhead of armoured horsemen set off. The purple draco writhed and snapped over them as they picked up the pace. The ground seemed to tremble beneath them.
A cavalry charge against infantry was a bluff. It was not so much that, once launched, it was almost impossible to stop, it was more that it surrendered the outcome to the other side. Horses do not run into solid objects. A line of men, shoulder to shoulder, two, three or more deep, was a solid object. One or two horses might be goaded or maddened enough to crash into it, but not several hundred of them. Unless the infantry ran, or at least were scared enough to flinch away, for gaps to open in their formation, the horses would pull up short. The magnificent charge would end up as a chaotic stationary mass; horses wheeling and plunging, riders thrown.
At least, thought Gallienus, as the Horse Guard thundered on, we do not have to cross our own caltrops to get at the nearest enemy. Not to have the right of the Roman infantry line throw caltrops had been a last-moment decision. Memor had pointed it out. The African protector would go far.
