Mardonius reoccupied Athens, Herodotus tells us (ix. 3), in the tenth month after Xerxes had taken it, that is to say not earlier than June of the next year. The pause in the war lasted therefore far beyond the winter. Both parties were no doubt anxious to gather the new harvest, but there were also other reasons for their delay.
Mardonius had been left in a difficult situation. The forces at his disposal were, it is true, still formidable. First, he had his own division, which we have seen reason to suppose was one of the six Persian corps ď armée, 60,000 strong. In confirmation of that estimate it may be noted that Herodotus assigns to him one sixth of Xerxes' army, which he conceives to have been the levy of the whole empire; and that if we compare the details of Mardonius' division (viii. 113, ix. 31.) with the catalogue of Xerxes' host (vii. 61–5), and reckon a myriad for each contingent of infantry (Immortals: θωρηκοφόροι: Medes: Sacae and Bactrians: Indians), we get 50,000 infantry, which with 10,000 cavalry gives the exact composition conjectured for a Persian army corps. The small drafts incorporated according to Herodotus from other contingents may be assumed, to have filled up the gaps made in the ranks by the first campaign. Second, Mardonius had his Greek auxiliaries, say 20,000 men, including the valuable Thessalian and Boeotian cavalry. Herodotus (ix. 32) estimates the Greek contingents at 50,000 men, but he expressly says that he has no authority for their numbers, and both probability and analogy (e.g. vii. 185, viii. 66) are against so high a computation.