27. Xerxes' famous expedition against Greece was again the result of the cabals and intrigues of the Greek exiles, the Pisistratidae, the soothsayer Onomacritus, the Thessalian princes or Aleuadae, who contrived to exert their influence on the king's mind, and to raise a party in their favour among the grandees. But the progress of the campaign showed that no Hippias was at the head of the invading army, although the Persian king did certainly succeed in his avowed object, the capture and destruction of Athens. Critique on the detailed account given by Herodotus of this expedition, as a national undertaking in which all the subjugated nations were obliged to take a share.--Preparations which last for three years in the Persian empire; league framed with Carthage for the subjection of the Sicilian Greeks, 483-481. The expedition itself in 480; over Asia Minor and the Hellespont, through Thrace and Macedonia.--Muster of the army and division of the troops according to nations at Doriscus; the detailed description of which found in Herodotus, was most probably borrowed from some Persian document.--The pass of Thermopylae taken by treachery; on the same day a naval engagement off Artemisium.--Athens captured and burnt. Battle of Salamis, Sept. 23, 480. Retreat of Xerxes; an army of picked men left behind, under the command of Mardonius.--Fruitless negotiations with the Athenians.--Second campaign of Mardonius: he is routed at Plataeae, Sept. 25, 479; and that event puts an end for ever to the Persian irruptions into Greece: on the same day the Persian army is defeated, and their fleet burnt at Mycale in Asia Minor. 28. The consequences of these repeated and unsuccessful expeditions, in which almost the whole population was engaged, must be self-evident. The empire was weakened and depopulated. The defensive war which the Persians for thirty years were obliged to maintain against the Greeks, who aimed at establishing the independence of their Asiatic countrymen, completely destroyed the balance of their power, by compelling them to transfer their forces to Asia Minor, the most distant western province of the empire. 29. Little as the Greeks had to fear from the Persian arms, the danger with which they were now threatened was much more formidable, when the enemy began to adopt the system of bribing the chieftains of Greece; a system which succeeded beyond expectation in the first trial made of it with Pausanias, and perhaps was not wholly unsuccessful with Themistocles himself.--But the Persians soon found in Cimon an adversary who deprived them of the sovereignty of the sea; who in one day destroyed both their fleet and their army on the Eurymedon; and by the conquest of the Thracian Chersonese, wrested from them the key of Europe.