By mid-morning the troops were assembled on the broad, level field beyond the camp ground. The British detachments had been the last to arrive at the muster, and joined similar detachments from each of the Rhine legions: I Minervia and XXX Ulpia Victrix, VIII Augusta and XXII Primigenia, I Martia and I Flavia Gallicana. Together they fielded almost five thousand heavy infantry, brigaded together with the irregular numeri of auxilia: the Batavi and Mattiaci, Frisiavones and Menapii, the Tungrian and Nervian archers. With the cavalry troopers of Equites Promoti, Mauri, Dalmati and Primo Sagittarii, the army mustered over ten thousand strong.
In the breeze the draco banners streamed against the clean-washed sky. From his position in the ranks with his men, Castus gazed along the lines of brightly painted shields, the glinting and glimmering of mail and scale armour, burnished helmets, honed spearheads. Trumpets rang out the imperial salute, and the assembled troops began throwing up their arms and cheering in acclamation. Castus cheered with them, feeling the lingering remorse and anxiety punching out of him with every breath.
‘Imperator Augustus! Imperator Augustus! Imperator Augustus!’
The emperor rode onto the muster ground at the head of his mounted bodyguard of Comites and Equites Scutarii, followed by his senior officers and the officials of the imperial household. Castus had not seen Constantine for nearly two years, ever since the strange and intoxicating days in Eboracum when the emperor had first been acclaimed by the troops after his father’s death. Back then, it had been hard to think of him as more than the tribune he had been. Now, Castus thought, Constantine looked in every way an emperor.
He rode slowly, on a powerful grey warhorse. His cuirass was gilded, glowing in the sun, and his purple cloak was woven with gold. A soldier rode behind him carrying his helmet, gold set with gemstones and decked with peacock-feather plumes. Constantine sat stiff in the saddle, barely moving his head to acknowledge the cheers as he rode between the ranks of his troops. His face looked flushed, raw-boned, his eyes deep-set.
Castus stared at the emperor as he passed, almost willing him to turn and see him there in the ranks. He remembered a previous meeting, back in the basilica of the headquarters in Eboracum. Constantine had recognised him then; would he know him again? Impossible, surely. But, even knowing all that he did about the murky background to the imperial accession, Castus was struck with a sense of awe. Emperors, he had been taught to believe, were like gods on earth. And Constantine had certainly come to appear like a god.
The imperial party reached the tribunal at the heart of the muster ground. Castus peered over the heads of his men, but could see little of the rituals that followed. Smoke rose from the altars, together with sounds of discordant trumpeting to deter evil spirits as the pig, sheep and bull were sacrificed to the gods of Rome. The omens were proclaimed as favourable, and then the standards were carried forward to the altar, to be anointed with the blood of the victims.
As he watched, craning his neck, Castus picked out another figure among the imperial party. A very large man, powerfully built, but ageing. He stood to one side, bare-headed, with a white and gold cloak drawn around him. His features were heavy, and he wore a thick dark beard, greying around the jowls. Castus had never seen him before, but he appeared somehow familiar. He noticed the way that the men around him, even the high officials, appeared to defer to him, or perhaps draw back from him slightly. A nimbus of stern authority surrounded him.
Now the emperor’s voice rolled out across the muster ground. The breeze stole away the words, but the troops did not need to hear them – they would learn soon enough what was expected of them. When the address was done the cheering commenced once more, and the last cries were still ringing across the churned turf as the imperial party mounted up and rode back towards the comforts of the city.
‘Two days from now,’ the tribune Jovianus announced, ‘our emperor will complete the bridge of boats across the Rhine and lead his field army against the Bructeri, the last of the Frankish tribes to remain in defiance of Rome. The intention is not only to punish them for daring to raid our provinces but to demonstrate the power of Roman arms to strike deeply into their lands, and break their power utterly.’
Twelve men sat before him on folding stools; others stood at the rear of the tent: centurions, and some of the commanders of the auxilia units. Castus was glad to see there was no sign of Urbicus or the other Second Legion men. Jovianus was standing, his staff clasped behind his back. He looked well bathed, his hair freshly dressed, and he wore a clean white tunic embellished with silver.
‘The barbarians will not be surprised at our coming,’ he went on. ‘They have expected Roman vengeance for over a year now, and their scouts are watching from the eastern bank of the river. They will already have seen the preparations for the bridge of boats, and will be assembling to resist us and ambush our vanguard troops as they cross. But what will surprise them is the speed and strength of our attack – they are always accustomed to flee at the first onslaught, and take shelter in their tangled forests, but, like a bolt of lightning, we will outpace them and destroy them!’
The tribune paused to allow his audience to digest what he had said. He clearly had aspirations, Castus reflected, to higher command – his style of speech suggested it. Through the open tent-flap came the late-afternoon sun and the sounds of camp life: men laughing as they gathered wood or cleaned weapons and equipment; lowing cattle; the distant neighing of horses from the cavalry lines. The familiar scent of the cooking fires too. Castus stared at the leather wall of the tent, as if he might be able to see through it. His empty stomach grunted and roiled.
‘To secure the bridgehead, therefore,’ Jovianus went on, ‘five hundred men of the Sixth Victrix and First Flavia Gallicana Legions, together with detachments of the Batavi and Mattiaci auxilia, will cross the river in small boats tomorrow night, three miles downstream. You will then make your way back southwards to the bridging area, and drive off any enemy force that you meet.’
A stir of muffled comments passed between the assembled officers. Castus saw the scepticism in their faces. They were veteran soldiers, and knew all too well the hazards of a river crossing, a march and an assault by night. Jovianus twitched his jaw, waiting for silence, then broke in, raising his voice slightly.
‘The task will not be easy! Absolute discipline must be observed. The crossing must be accomplished in total silence, to avoid alerting the barbarian scouts to our stratagem. Once on the far bank of the river, the boat parties must assemble, maintain formation, and reach the enemy positions before dawn. Keep the river directly to your right and you will not stray. The night should be clear, so you will have the stars to guide you.’
‘And the moon to guide the Frankish scouts to us,’ Valens whispered. Jovianus paused a moment, as if daring anyone else to comment, then went on.
‘Your men will be lightly equipped, without armour, to move fast and silently. In order to sow confusion and terror among the barbarians, each century will move as a separate unit. In this way, you will attack the enemy at many points simultaneously, and make them believe that the entire Roman army has beset them. When all enemy forces have been routed from the far side of the river, you will signal using trumpets, then the engineers will complete the construction of the bridge and the army will commence crossing at first light.’
Jovianus squared his shoulders, rocked back on his heels and inhaled through his nose, obviously very pleased with the plan. As if, Castus thought, he had devised it himself. Perhaps he had?