The operations of the fleet described in the last chapter, and those of the army narrated in this, took place, it will be remembered, at the same time, and in the same vicinity too; for, by referring to the map, it will appear that Thermopylæ was upon the coast, exactly opposite to the channel or arm of the sea lying north of Euboea, where the naval contests had been waged; so that, while Xerxes had been making his desperate efforts to get through the pass, his fleet had been engaged in a similar conflict with the squadrons of the Greeks, directly opposite to him, twenty or thirty miles in the offing.
After the battle of Thermopylæ was over, Xerxes sent for Demaratus, and inquired of him how many more such soldiers there were in Greece as Leonidas and his three hundred Spartans. Demaratus replied that he could not say how many precisely there were in Greece, but that there were eight thousand such in Sparta alone. Xerxes then asked the opinion of Demaratus as to the course best to be pursued for making the conquest of the country. This conversation was held in the presence of various nobles and officers, among whom was the admiral of the fleet, who had come, with the various other naval commanders, as was stated in the last chapter, to view the battle-field.
Demaratus said that he did not think that the king could easily get possession of the Peloponnesus by marching to it directly, so formidable would be the opposition that he would encounter at the isthmus. There was, however, he said, an island called Cythera, opposite to the territories of Sparta, and not far from the shore, of which he thought that the king could easily get possession, and which, once fully in his power, might be made the base of future operations for the reduction of the whole peninsula, as bodies of troops could be dispatched from it to the main land in any numbers and at any time. He recommended, therefore, that three hundred ships, with a proper complement of men, should be detached from the fleet, and sent round at once to take possession of that island.
To this plan the admiral of the fleet was totally opposed. It was natural that he should be so, since the detaching of three hundred ships for this enterprise would greatly weaken the force under his command. It would leave the fleet, he told the king, a miserable remnant, not superior to that of the enemy, for they had already lost four hundred ships by storms. He thought it infinitely preferable that the fleet and the army should advance together, the one by sea and the other on the land, and complete their conquests as they went along. He advised the king, too, to beware of Demaratus's advice. He was a Greek, and, as such, his object was, the admiral believed, to betray and ruin the expedition.