"We take them from behind!" he cried. "For Mars and Mithras, charge!"
The line of Roman cavalry burst from the trees as if the forest had exploded, shields on the left arm, lances leveling on the right, the sound of hooves on frozen ground thundering like barbarian drums. The hundreds of Celts before them were milling in confusion in front of Hadrian's Wall after being hurled back from the burning gateway. Warnings were shouted, warriors turned, and they looked at his cavalry charge at their rear in horrified wonder, each individual barbarian deciding whether to fight or run.
Run where? The Wall and its rain of arrows were at their backs.
Marcus's own line widened as each trooper picked a target and aimed his lance.
Many Celts howled defiance, of course, running to meet this new threat with the fatalism of the condemned. Shields were raised and swords brandished. Their tactical hopelessness was perversely giving them maniacal courage. They'd fight as berserk individuals, and that, the Roman knew, would prove their undoing. They fought with bravery, but not with thought. And so they were doomed, or so Marcus hoped.
The cavalry first ran down some camp followers and wounded at the rear of the barbarian mass, the victims screaming in terror as the thrashing mill of hooves chewed over them. Then came a ragged line of defiant warriors, shields up, axes poised, a few of their arrows striking home and spilling some of Marcus's cavalry from their saddles. Brisa had pulled the shaft from her own arm and found another bow. Now, desperate and heedless of the flow of her own blood, she was firing as fast as she was able.
It wasn't enough. The Romans simply ran over them. The woman saw a blur of horseflesh, a maelstrom of hooves, and then she was under and trampled, blacking out. There was another concussive collision, its sound like a clap of thunder, and the two armies north of the Wall were shredded together as they were to the south, lances impaling the Celts who didn't dodge fast enough, horses screaming and toppling, men butted aside like dolls. The power and weight of the cavalry shattered the barbarian formation, and the Romans shouted fierce satisfaction as they wheeled their horses to work with their swords. The blades rose and fell in awful rhythm, like the arms of a primitive machine.
Marcus expertly guided his horse through the confusing combat, its horror more familiar now after the battle in the grove. He feinted as if to pass to the right of a painted barbarian carrying a two-handed broadsword, then cut his horse to take the man by surprise on his left. The praefectus's shield arm went out to fend off the barbarian's blow even as his own spatha swung in a great deadly arc. The handle stung as it chopped into muscle and bone. The barbarian screamed and went down. Then Marcus was beyond him, using the prancing hooves of his excited horse to push more of the barbarians into the cold river, trampling some underfoot. He saw a javelin catch one young cavalryman in the back, spilling him, but then another Roman rode up and cleaved the thrower's head.
The Romans on the Wall were roaring encouragement and firing arrows. On both sides now the Roman cavalry was chopping up the split attack. Soon the Celts must surrender into slavery or be met with certain death. Some of the demoralized barbarians sought shelter toward the smoking ruins of the gate archway, only to meet Roman legionaries dropping down from the crest above.
"Victory, Marcus Flavius!" the centurion Longinus called. "We have them!"
And then Celtic horns sounded again.
More than a thousand men and women had followed Arden Caratacus in the first assault at what he'd been assured would be a weakly defended gate. It was this thousand that was in desperate straits, cut in two and fighting for their lives against a smaller but far more disciplined and better-positioned Roman force. Hundreds were already dead and wounded, and annihilation seemed a real possibility.
But a thousand more Celtic warriors had been secreted in a nearby ravine, including almost all the horsemen who represented the best and wealthiest of barbarian warriors. Galba hadn't told Arden of the ambush he'd meet after breaking through the Wall, but he had told the barbarian about the flanking attack by Marcus, explaining that the praefectus intended to fall upon their rear. The charge by that wing of the Petriana was no surprise.
This rear was bait, in other words, and the Celts were determined to make the Roman trap a trap of their own. Now out of the trees to the north came the barbarian horses in wild attack against the rear of the preoccupied Roman cavalry, followed by hundreds of additional infantry on foot. They were going to surround the Petriana as it had tried to surround them.
The soldiers on the Wall sent up shouts of warning at the approach of this new onslaught, but most of Marcus's cavalry were fighting too desperately to pay attention. There was a wild wavering cry, a call to their gods as chilling as death itself, and then the Celtic horses crashed into the Latins like an avalanche, toppling Romans from their mounts before they had a chance to turn or form or escape.
In an instant the barbarian foot soldiers, who'd been overmatched by Roman cavalry, turned on their dismounted foes and chopped in a frenzied spray of blood.
Marcus's own horse was driven into the bloody river Ilibrium by the impact of the attack. He was confused as to what was happening. Where had all the barbarians come from? At one moment victory had been in his grasp. A moment later his cavalry seemed mired in a sea of Celts, arrows and spears whistling past and horses screaming in terror as they were gutted. The barbarians who'd been demoralized only moments ago were now hoisting weapons for revenge. Even some of the wounded were picking themselves off the ground to fall on the Romans again.
"Marcus, we've got to retreat!" cried Longinus, hauling the head of his horse around to bolt. Yet even as he did so a red-haired chieftain in horned helmet galloped by and hit the centurion's horse with a two-bladed ax, knocking animal and rider into the cold water of the river. With a splash, they went under.
Longinus struggled to get out from under his dying horse, kicked free, and surged up onto the bank, sputtering. His spatha was gone. The barbarian came at him again, missing the centurion with his main blow but chopping into his foot, and so he screamed and went down once more, sliding into the water. A red plume ran off his wound.
Marcus rode up and took off the barbarian attacker's arm with his sword, its artery spewing like a fountain. The Celt bellowed, reeled, and lurched off his saddle.
Then the praefectus jumped off his horse into the icy river and seized the half-drowned centurion, pulling Longinus across the Ilibrium and onto the bank nearest the Wall. The battle had become a nightmare. His men were being unhorsed. The pennants and standards of the Petriana were falling like toppled trees into a mob of screaming, excited Celts. The tide of battle had reversed once more. Arrows were falling everywhere, each side hitting both foes and comrades in the confusion.
Then his own deserted horse was down, a spear in Homer's side, and any chance of escape was gone. "We need to get under the Wall! We'll seek protection there!"
He began dragging the wounded Longinus up the bloody slope. It was littered with bodies, Celtic and Roman, and the centurion left his own trail of blood from a foot half severed. A few Romans saw what their commander was doing and formed a protective ring around him to help, but this concentration only drew more enemy fire. The guards began to topple over as arrows struck home.
Marcus was dragging Longinus with one hand, hacking with another. There was a blow to his thigh, and he stumbled, dimly realizing that he was wounded. It was surprising that it didn't yet hurt. He panted from the labor.
Finally the stonework of Hadrian's Wall loomed above him. Cavalrymen were fighting desperately with Celts who'd taken their own shelter in the burnt passageway, both sides wrestling for the refuge.