Once his armies set foot on that far shore, that slender peninsula, they could march through Thrace and west into Macedonia, into lands they did not know, coming south at last to crash against the cities of Greece like a great wave. Xerxes had not forgotten his father’s vow. King Darius had left only one thing unfinished, in all the richness and wonders of his life. Death had stopped him, but a man’s sons could still act after his death! That was the very purpose of sons, to cheat the natural ending of ambition. Xerxes smiled at the thought. He had put his seed into the belly of his wife before leaving the heartlands. Amestris had promised him a son, a crown prince he could raise to greatness, as Darius had done. To make certain, she had buried seven boys alive, taking them from the families of small kings. It was a grand sacrifice, he thought, a gesture typical of her and touching in its faith. Perhaps, too, it was a reminder for him to be faithful. His father had once warned him to be wary of a woman who might watch while he slept. All the strength and authority in the world were as nothing while a man snored.

The breeze picked up, stirring dust around his feet as it passed by. Xerxes shaded his eyes and looked at the immense labour still continuing below. He had not failed to honour his father. That simple truth was written in the regiments moving like beetles on the land, in the great fleet that bobbed at anchor and grew every month. The labour and the costs and the training were sums unimaginable. Xerxes had sent his accountants away in the end, when they had grown worried and fearful. What was the purpose of wealth if not to make war on the enemies of his people? What good did it do to eat from plates of gold, to sip wine from jewelled cups, if Greeks still lived and laughed and scorned his father’s memory? Xerxes had no need for a slave to whisper into his ear each evening. He could not forget the Greeks. In his dark times, he wondered if the defeat at Marathon had brought on the illness that had led to his father’s death.

Xerxes found himself clenching his fists. He opened them slowly, seeing his palms had whitened with strain, like dead flesh. He had made one final attempt at emulating the greatness of his father. He had sent men in peace to every Greek city, offering vassalage, for dust and water. If Athens and Sparta had accepted his rule over them, he would have shown kindness, in his father’s name. He told himself it was true. Darius had made him understand he had to be more than a king to rule an empire. He had to do everything he could to appear merciful. More, if they allied themselves to him, his new subjects had to be certain he would protect them, even against their own.