In
Ionia (the modern Aegean coast of
Turkey) the Greek cities, which included great centres such as
Miletus and
Halicarnassus, were unable to maintain their independence and came under the rule of the
Persian Empire in the mid-6th century BC. In 499 BC the Greeks rose against the Persians in the
Ionian Revolt, and Athens and some other Greek cities went to their aid, though they were at forced to back down following their defeat in 494 BC at the
Battle of Lade. The Greek cities in Asia Minor returned to Persian control. In 492 BC, the Persian generals
Mardonios and
Datis launched a naval assault on the Aegean islands, causing them to submit, then unsuccessfully attempted to disembark at Marathon in 490 BC to take Athens. In 490 BC, the Persian Great King,
Darius I, having suppressed the Ionian cities, sent a fleet to punish the Greeks. Hundred thousand Persians landed in
Attica, attempting to take Athens, but were defeated at the
Battle of Marathon by a Greek army of 9000 Athenian
hoplites and 1000 Plateans led by the Athenian general
Miltiades. The Persian fleet continued to Athens but, seeing it garrisoned, decided not to attempt an assault. During the subsequent period of peace, in 483 BC, a silver-bearing seam had been discovered in the
Laurion (a small mountain range close to Athens), and the hundreds of
talents mined there had paid for the construction of 200 warships to fight
Aegina's piracy. In 480 BC, Darius' successor
Xerxes I sent a much more powerful force of 300,000 by land, with over 1200 ships in support, across a double boat-bridge over the
Hellespont. This army took Thrace, before descending on Thessaly and Boetia, whilst the Persian navy skirted the coast and resupplied the ground troops. The Greek fleet, meanwhile, dashed to block the Persians at Cape
Artemision. After being delayed by the Spartan King
Leonidas I at Thermopylae, Xerxes advanced into Attica, where he captured and burned Athens. But the Athenians had evacuated the city by sea, and under
Themistocles they defeated the Persian fleet at the
Battle of Salamis. In 479 BC, the Greeks, under the Spartan
Pausanias, defeated the Persian army at
Plataea. The Athenian fleet then turned to chasing the Persians out of the Aegean Sea, defeating their fleet decisively in the
Battle of Mycale, and in 478 BC the Athenian fleet captured
Byzantium. In the course of doing so Athens enrolled all the island states and some mainland allies into an alliance, called the
Delian League because the League's treasury was kept on the sacred island of
Delos. The Spartans, although they had taken part in the war, withdrew from any further involvement, allowing Athens to become the unchallenged naval and commercial power in the region. ==The Delian League and Athenian dominance==