Xerxes had told him to bring the Greeks to heel, to make them bend the knee and acknowledge the empire. Mardonius set his mind to fulfilling the task he had been given. After a time, he found he was enjoying himself. It felt like a weight lifting, to have a problem that needed his wit and experience to solve. No, it was more even than that. He had been so long under the gaze of Xerxes that Mardonius had almost forgotten the simplest reward of authority. As a breeze blew across his face, he let peace flood through him. He was in command, of all the forces in Greece. He was free – free to fail and starve, yes, but also to triumph and know the achievement was all his own. Mardonius was on campaign, with strong sons and trusted men! For an old warhorse like himself, it was not too great a burden.

A few of his horsemen blew horns ahead, dragging his thoughts back to the present. Over to the west, Mardonius squinted into the distance, seeing a haze of dark blue, but also a dun line – the wall across the famous isthmus. Mardonius tasted acid when he understood the dots of colour were red-cloaked Spartans, watching his people. He muttered a curse at them and spat on the ground.

He had not realised his regiments would pass quite so close to the neck of land that separated the Peloponnese from the rest of Greece. He recalled Artabazus had said something along those lines, but the reality was still surprising. All the Persian officers had heard of the wall the Spartans had built. Mardonius scowled, recalling how he’d laughed on first hearing of it. It would have availed them little when a Persian fleet could land anywhere on their rocky coast! Of course, that fleet lay at the bottom of the strait at Salamis, or as driftwood still appearing on every beach of the Aegean. The Spartans had made a poor choice with their wall, only to have it become a stroke of genius. It was enough to make a man believe in their gods …

With his enemy watching, Mardonius felt a pang of regret at his marching formation. He had the men in over two thousand ranks, each eighty or a hundred deep. It made a great snake of a column when crossing unknown land, but it would not look quite as intimidating as he might have wished. Still, it took hours for them all to pass the distant Spartan line. Let them observe that! Regiments of Persian horsemen swirled around the edges and thick dust hung in the air for half a day.