The Persian cavalry had vanished back, carrying tales to their master. Only a few remained to observe the hoplites and their strange companions. Their spears had all been thrown and those young men could only glare and sneer. Aristides jogged through to the fore, where his hoplites marched in ranks four deep, a bronze skin across the face of the helots. He kept pace with the front rank of those, observing his men just ahead. His Athenians made a grand show as they marched, spears flashing, bronze gleaming gold. He was proud of them.

Aristides felt his stomach drop away as a thought struck. He did not know if he was marching to battle in that very moment – and if he was, whether the helots would stand, or break and run at the first battle shout. Could he ever understand such men? They had been born to slavery. They were only there because Pausanias did not want to leave so many at home in Sparta! As Aristides strode along with them, he wondered if they had anything like officers among their number. It was the natural estate of men to raise one or two to lead the rest. Did that apply to those who lived as slaves? He looked at the closest one, just a couple of paces away. The helot was a short, hairy fellow, with black eyes and a nose like a blade.

‘Can you fight at all? You helots?’ Aristides called to him.

The man ducked his head when he understood he was being addressed, the reaction of an oft-beaten dog. Aristides tried again.

‘If the Persians come, will your people stand? Should I send you back to your masters on the slopes? You have just a few shields and spears.’

The sullen helot still didn’t reply. Aristides reached to take him by the arm and the man shook him off and moved sharply away, vanishing amongst his people.

‘Why should we stand?’ another of them said suddenly.

He was younger, with scarred hands and a deeply puckered muscle on his thigh that spoke of old wounds, badly healed. He limped, Aristides saw, giving him a rolling gait.

‘Are the Persians our enemy?’ the man said. ‘Why? What have they ever done to us?’

‘They will water this dry ground with your blood if you run,’ Aristides said curtly. ‘There is that.’

‘You’d have us fight without shields? For you, is it? For the Spartiates?’

Aristides regarded him for a time. On another day, he might have enjoyed debating the point, perhaps on the Pnyx hill, with Themistocles, Xanthippus and Cimon all there to make their observations. Yet in that place, hoplite and helot marched towards a vast and hostile enemy camp, already roused against them. He had no patience to build an argument of force and persuasion. War took everything he loved, he realised. Everything that made life worthwhile. Anger surged in him, sharpening his thoughts.