Some of the Nubians tried to surrender, throwing down their weapons and holding out their empty hands as they pleaded for their lives in their tongue. To no avail. They died alongside their comrades who fought on, hampered by the stifling press of men, which made it impossible for them to wield their weapons effectively.

For more than an hour it continued as the Roman cordon closed round those still trapped, Prince Talmis amongst them. The auxiliary cavalry had blocked their retreat and speared those who tried to get past them. Occasionally small groups of fugitives did manage to thrust past the horsemen, but the survivors were allowed to escape and the landscape to the south was dotted with figures running for their lives. As midday approached, the killing began to slacken as the Romans became too weary to continue the slaughter. Some of the Nubians took advantage of this and slipped between men who made no effort to stop them. Cato rode forward and his horse had to pick its way carefully over the bodies as it crossed the killing ground.

‘Stand to! Centurions, call your men to their standards!’

He saw Macro, spattered and smeared with crimson, leaning on his shield, chest heaving as he gasped for breath. ‘Centurion! Let the enemy pass. All except the Prince and his bodyguard. And the gladiators. They mustn’t escape. Understand?’

Macro nodded, blinking away the sweat that dripped from his eyebrows. He pulled himself up and lifted his shield as he turned to address his men. ‘Form ranks!’

The men of the First Cohort wearily trudged back to their standards and waited for orders. Cato felt a bitter weight in his heart as he saw that less than half of the men remained. The reserve cohort that had rushed to fill the gap had suffered a similar proportion of casualties. Macro waited until the last of his men was in position and then ordered them to advance on the standard of Prince Talmis. Cato’s horse shied at the mounds of bodies that lay in his path and he dismounted and made his way to Macro’s side.

‘Well, the plan worked.’ Macro smiled wearily. ‘Never thought I’d see the day when I’d be grateful to Hannibal.’

‘It’s not quite over yet.’ Cato nodded towards the knot of bodyguards gathered around the Prince’s standard.

Macro shrugged. ‘They’re finished, one way or another. Surrender or die, Talmis is ours.’

The Romans opened their ranks to let the last of the lightly armed Nubians and Arabs flee, and then closed in around the bodyguards. They were big men, with scale armour and conical helmets. They carried oval shields and heavy spears and stood shoulder to shoulder as the Romans advanced on them.

Cato raised his arm as they came within twenty paces of the standard. ‘Halt!’