At the time of his departure the issue of the struggle was as yet unforeseen.  Mardonius evacuated Attica, which was too poor and desolate a country to support so large an army, and occupied comfortable winter quarters in the rich plains of Thessaly, where he recruited his strength for a supreme effort in the spring.  He had with him about 60,000 men, picked troops from all parts of Asia—­Medes, Sakae, Bactrians, and Indians, besides the regiment of the Immortals and the Egyptian veterans who had distinguished themselves by their bravery at Salamis; the heavy hoplites of Thebes and of the Boeotian towns, the Thessalian cavalry, and the battalions of Macedonia were also in readiness to join him as soon as called on.  The whole of these troops, relieved from the presence of the useless multitude which had impeded its movements under Xerxes, and commanded by a bold and active general, were anxious to distinguish themselves, and the probabilities of their final success were great.  The confederates were aware of the fact, and although resolved to persevere to the end, their maoeuvres betrayed an unfortunate indecision.  Their fleet followed the Persian squadron bound for the Hellespont for several days, but on realising that the enemy were not planning a diversion against the Peloponnesus, they put about and returned to their various ports.  The winter was passed in preparations on both sides.  Xerxes, on his return to Sardes, had got together a fleet of 200 triremes and an army of 60,000 men, and had stationed them at Cape Mycale, opposite Samos, to be ready in case of an Ionian revolt, or perhaps to bear down upon any given point in the Peloponnesus when Mardonius had gained some initial advantage.  The Lacaedemonians, on their part, seem to have endeavoured to assume the defensive both by land and sea; while their foot-soldiers were assembling in the neighbourhood of Corinth, their fleet sailed as far as Delos and there anchored, as reluctant to venture beyond as if it had been a question of proceeding to the Pillars of Hercules.  Athens, which ran the risk of falling into the enemy’s hands for the second time through these hesitations, evinced such marked displeasure that Mardonius momentarily attempted to take advantage of it.  He submitted to the citizens, through Alexander, King of Macedon, certain conditions, the leniency of which gave uneasiness to the Spartans; the latter at once promised Athens all she wanted, and on the strength of their oaths she at once broke off the negotiations with the Persians.  Mardonius immediately resolved on action:  he left his quarters in Thessaly in the early days of May, reached Attica by a few quick marches, and spread his troops over the country before the Peloponnesians were prepared to resist.  The people again took refuge in Salamis; the Persians occupied Athens afresh, and once more had recourse to diplomacy.  This time the Spartans were alarmed to good purpose; they set out to the help of their ally, and from that moment Mardonius