His fleet and army then passed across the Hellespont. Here, Herodotus writes that the fleet was destroyed in a storm off of Mount Athos; and the Persians lost 300 ships and 20 000 men. Mardonius himself was commanding the army at the time, which was fighting a battle in Thrace. Mardonius was wounded, but was victorious. The navy and the army
continued to Macedonia, which was added to Darius' kingdom as well. After his enormous victories and partly as a result of the loss of his fleet in the strom he retreated back into Asia Minor. Mardonius had been very successful. There are indications that his army reached the Danube, because an Old Persian inscription was discovered near Kölmer in Rumania. (The possibility that the inscription was brought to Rumania from its original site, however, can not be ruled out.) The conquest of Macedonia was important, as it was a fine base for further conquests in Europe and posessed gold mines. Darius was fully entitled to claim in his inscription at Naqš-i Rustam that he had conquered the Yaunâ takabarâ, the 'Greeks with sun hats', a reference to the Macedonian headwear.
In 490, the Persians conquered the islands in the Aegean Sea, but Mardonius, who had already lost a fleet, was not in charge of this expedition. The 600 ships were commanded by Datis and Artaphernes. Herodotus again presents the expedition as a punitive action against Eretria and Athens, who had supported the Ionian revolt. But he is almost certainly wrong, because the army was too small to attack Athens. In reality, the aims of the expedition of Datis and Artaphernes were to add the Aegean island Naxos to the empire, and, in doing so, to create a buffer zone between Ionia and the Greek mainland. They also had to conquer Euboea (with its capital Eretria) and bring back the former ruler of Athens, the pro-Persian tyrant Hippias. The expedition succeeded brilliantly. Except for their last objective, everything went according to plan.
Having conquered Macedonia and the Aegean islands, Darius could attack the Greek mainland whenever he desired. This would be a difficult expedition because the Greek soldiers were better equipped than the Persians and their subjects. Therefore, the Persians had to muster a very large army, but king Darius the Great died shortly before it was to set out (November 486). He was succeeded by his son Xerxes
, Mardonius' cousin and brother-in-law.
Mardonius came back into favour under Xerxes I
. Xerxes was at first not interested in renewing the war with Greece, but Mardonius repeatedly tried to convince him that he must avenge Darius' defeat, in opposition to another advisor, Artabanus, who urged more caution in the matter. Herodotus, who portrays Mardonius as somewhat of an evil advisor (as opposed to a number of other good advisors whose arguments are never followed), says that Mardonius simply wanted to become the governor of Greece.
Right before the expedition to Greece however, a rebellion in Egypt started, postponing the newly formed expedition plans. Immediately after this revolt, Xerxes
, Mardonius, Megabyzus and four other commanders could go to the west, where a large army was gathering in Sardis.
The first year of the expedition was a big success. The Persians were not in a hurry, because they had an enormous army (about 600,000 men) and had to wait for the harvest in Thrace and Macedonia. In July and August, they stayed at Therma (Thessaloniki), and then moved south to Greece. Thessaly was conquered without much troubles, and on 17, 18 and 19 September (or one day later) a double battle took place. The Persian navy was able to drive the Greek navy away from its positions at Artemisium, and the army destroyed the Greek garrison at Thermopylae.
Boeotia was added to the Achaemenid empire, and on September 27, Athens was captured; next day, the acropolis fell and the Persian navy ocuupied the Athenian harbor. Persian cavalry destroyed the sanctuary of Poseidon near Corinth and fired burning arrows at one of the Corinthian harbors.Xerxes'
victory was almost complete. The Greek navy had fled to Salamis, an island opposite the harbor of Athens, separated from the mainland by a narrow strait. Unfortunately, when a part of the Persian navy tried to attack the Greek positions on Salamis, they suffered heavy losses. This was a minor setback. At this point, Herodotus writes that after the loss at Salamis, Mardonius attempted to convince Xerxes
to stay and fight yet another battle. This time he could not persuade Xerxes, but when Xerxes
left he did become governor of the parts of Greece that had been conquered. In the Persian accounts, Xerxes
motive for retreating from the war was unsettelments at Babylonia. There were disturbing rumors, and Xerxes
decided that it was better that he went back to Sardes, where he could keep an eye on both Greece and Babylonia. It was a wise decision. In the summer of 479, the Babylonians revolted again (this time, their leader was Šamaš-eriba) and Xerxes
had to suppress their rebellion.
Meanwhile, Mardonius was left in charge of the Persian army in Greece. His army was comparatively small, probably 150,000 men. After all, the main army was needed at the main battle ground, Babylonia. To feed his men, he had to retire to Thessaly, from where he opened negotiations with Athens. He offered the town a beautiful position in the Achaemenid empire if only they recognized the overlordship of king Xerxes
. It was a brilliant move, because if the Athenians accepted this offer, there was no navy to protect southern Greece anymore. The Athenians had much to gain from the deal, because they would become the most important city state in Greece. However, they stubbornly refused.
In the spring, Mardonius marched to the south again, reoccupying Boeotia and moving to Athens. He hoped that the Athenians would be more forthcoming, but he was wrong. Having received a new refusal to surrender, Mardonius plundered Athens. (Archaeologists digging in Persepolis have discovered a statue of Penelope that was probably taken away from Athens.)
It seemed that Mardonius was master of the situation. The Spartans, who had the best infantry of Greece, refused to assist the Athenians. It was only after an ultimatum by the Athenians that if they did not come to their help, they would be forced to surrender and give their navy to Mardonius, that Sparta acted. It sent an army to the north and invited all Greeks to join in the struggle for the liberation of Greece.
The Greeks gathered in the south of Boeotia, on the foothills of the Kithaeron mountain range. Their counted some 100,000 soldiers; almost every Greek able to carry weapons had come Boeotia. For example, the Athenians had manned only a few galleys; all rowers and marines were now on Mount Kithaeron. This Greek army was unable to move into the plain, because they could not afford to go far beyond the sources at the foothills. After all, August can be very hot in Greece. Since no side dared to advance, a war of nerves started.
Herodotus, who is our main source for the battle of Plataea, describes several engagements that take place on several days. A Persian cavalry squadron tried to provoke the Greek contingent from Megara, but was defeated. After this success, the Greeks decided to leave the mountains and to descend into the plain between the river Asopus and a small town called Plataea, where a large source in the middle of the plain (near the hill in the middle of the map) would refresh them. All this time, the two armies refrained from real attacks, because they received the same omens: they would only be victorious when the other side attacked first (and moved away from its water supply).
Mardonius however, was in a hurry. His supplies were running out, he could see the Greek army growing every day and one of his advisors has already suggested to return to Thessaly and use gold and silver to bribe the Greek leaders. Mardonius would have none of it: he still hoped to settle the matter with honorable, military means.
To stop the growth of the other army, he unexpectedly and successfully attacked a large supply train in the Kithaeron. Short cavalry charges, meant to provoke his enemies into battle, were executed, but the Greeks wisely resisted the temptation.
Herodotus tells that one night, a Persian ally, the Macedonian king Alexander, came to visit the Athenians, telling them that the Persians would attack at dawn. Immediately, the Athenian officers informed the supreme commander of the Greeks, the Spartan prince Pausanias. He understood that if the Persians attacked, it would be saver to have the well trained Spartans on the defensive left wing to counter the Persian main force, and to post the experienced Athenians -already victorious at Marathon- on the offensive right wing. At dawn, the two contingents changed positions. After reports of a Persian counter-manoeuvre, the two Greek contingents return to their original positions.
He seems to have misunderstood the incident. It is implausible that Alexander of Macedonia could leave the Persian camp without being seen. It is likelier that Mardonius sent the Macedonian king on his mission. It was a brilliant trick to create panic among the Greeks, who started all kinds of exhausting movements.
In this way, the day passed without fighting, and Mardonius became even more anxious to attack. During the night, his mounted archers attacked the source between Plataea and the Asopus, hoping to force the Greek troops to go back to the south, to the sources on the slopes of the Kithaeron mountains. They stood their ground during the day -being continually harassed by the Persian archers- but after sunset, they retreated as Mardonius had planned.
At dawn, Mardonius learned that his opponents had fled, and thinking he had already won the battle, ordered the pursuit of the Greeks. He first attacked the Spartans, who were forced back. Pausanias even had to sent a messenger to ask the Athenians for help, but they were unable to offer assistance, because they were intercepted by Mardonius' Greek allies. One of the Persian contingents even broke through the Greek battle array and reached the foothills of the Kithaeron.
At this moment, while he was pursuing the retiring Spartans, Mardonius was killed. It is not known how this happened, but we can be sure that Mardonius, who knew that his army had been victorious, died as a happy man.
This incident changed the battle, because the Persians lost courage, which gave the Spartans a brief pause. They were able to regroup and attack the Persian contingent in front of them. The struggle did not last long: the demoralized Persians took their heels. The Persian camp was captured by the Athenians, and that meant the end of the war. One of Mardonius subordinates, Artabazus, was able to lead a large Persian contingent back to Asia, for which he was rewarded by Xerxes, who offered him the satrapy of Hellespontine Phrygia, i.e., the northwest of what is now Turkey.
Herodotus has a very strange story to tell about an event that took place after the battle.