Andonnoballus had told Valens that this was a hunting expedition. Naulobates had not wished to arouse suspicion among the Persians at his long journey to their frontier, at the very south-east of his domains. When the King of the Heruli went hunting, it was not a matter of a few friends and dogs. Naulobates was accompanied by ten thousand warriors, and each of them had brought at least five remounts.

As they approached, Valens spotted a lookout stationed high in a tree. It seemed an unnecessary precaution, given that Andonnoballus had left half his troop – no fewer than a thousand riders – strung out across the Steppe south of the burial mounds. Nothing could leave the Walls of Alexander without the Heruli being informed. All the tribes between the Caspian and the Aral Sea were subject to Naulobates. Perhaps their allegiance was uncertain.

There were only a few places where a rider could descend with safety into the bed of the river. Andonnoballus led them down a sandy, well-trodden draw, and called in his native tongue to the man perched among the topmost branches. The warrior replied in a sorrowful tone. Andonnoballus and the other Heruli laughed with little sympathy.

‘He will stay there until dawn tomorrow,’ Artemidorus explained to Valens.

‘Why not relieve the sentry more often?’

This provoked a gale of merriment among the tribesmen.

‘He is not a sentry.’ Artemidorus could hardly talk for laughing. ‘It is a punishment. He must cling there from one dawn until the next.’

‘What was his crime?’

‘Before we left our winter grazing, he attacked Uligagus.’

‘Nothing wrong done by me.’ The Greek of the big shaggy Uligagus was not as good as the others. ‘Hung gorytus outside tent. Enjoying his wife. All quite proper. Come in and attacks me, unproven.’

‘Unprovoked,’ Artemidorus corrected.

‘Yes, that. Gave him good beating.’

‘My father showed clemency,’ Andonnoballus said. ‘In the past, Naulobates has had men torn apart for such a thing.’

‘Torn apart?’

‘Two saplings are bent down. One of the criminal’s legs is tied to each. Then you let them go.’

‘There can be no jealousy or mistrust among the brothers,’ Artemidorus added.

‘What if he falls from the tree?’ Valens asked.

‘It is a long way down.’

They were shown to their quarters. Three tents at the north-western edge of the camp away from the river had been assigned to them. One was for Valens, the second for the other officer, Decimus, the final tent for the four soldiers. The shelters were made of felt stretched over a round wooden frame. There was a hearth in the centre, and a hole at the top. If the smoke got too much, drawstrings could raise the sides. Although their design was unusual to the Romans, the tents were clean and well appointed. The mission stacked their saddles and tack, as well as what little baggage remained to them, against the walls opposite the entrances.

‘When will your father receive us?’