The scouts swung into line with their legate and charged obliquely across the incline towards the lightly armed Durotrigans. Ahead of the horsemen the Britons were already scattering, their roars of triumph dead on their lips. Vespasian saw that the commander of the convoy had made good use of the diversion and the wagons were once more rumbling towards the safety of Calleva’s ramparts. But the leader of the Durotrigans was no fool either, and a quick glance revealed to Vespasian that the heavy infantry and chariots were already moving towards the convoy to strike before their prey reached the gates. A short distance to his front, woad-stained bodies weaved madly, desperately trying to avoid the Roman horsemen. Vespasian fixed his sight on a large slinger wearing a wolfskin around his shoulders, and lowered the point of his sword. At the last moment, the Briton sensed the horse bearing down on him, looked round sharply, eyes wide with terror. Vespasian aimed his blow a short distance down from the man’s neck and braced his arm for the impact, but at the last moment the slinger threw himself flat and the blade missed.

‘Shit!’ Vespasian hissed through clenched teeth. These bloody infantry swords were no good on horseback, and he cursed himself for not carrying a long cavalry sword as his scouts did.

Then another enemy warrior was in front of him. He just had time to register the thin, frail physique and white spiked hair before he slashed his blade into the man’s neck with a wet crunching sound. The man grunted and tumbled forward, and was gone as Vespasian galloped on towards the convoy. He snatched a glimpse at his scouts, and saw that most had reined in and were busy thrusting their spears at any Briton they could find cringing on the ground. It was the perfect moment for any cavalryman: the killing frenzy that followed the breaking of the enemy line. But they were heedless of the danger of the chariots that were even now trundling across the slope towards the small party of Roman horsemen.

‘Leave them!’ Vespasian roared. ‘Leave them! Make for the wagons! Go!’

The scouts’ senses returned to them and they closed ranks, and galloped after Vespasian as he made for the rearmost wagon, no more than a hundred paces away. The auxiliaries in the rearguard raised a ragged cheer and waved them on with their javelins. The horsemen had almost reached their comrades when Vespasian heard a faint whirr, and the dark streak of an arrow shot by his head. Then he and his men were in amongst the wagons, halting their blown horses.

‘Close up! Close up at the rear of the convoy!’