Greco-Persian Wars: Battle of Marathon 490 BC | 25,000 Persians, under King Darius' generals, landed on the Greek Plain of Marathon.
When Greek colonists set out from mainland Greece, many wound up in Ionia, in Asia Minor. In 546, the Persians took over Ionia. Ionian Greeks found the Persian rule oppressive and attempted to revolt with the aid of the mainland Greeks. Mainland Greece then came to the attention of the Persians, and war between them ensued.
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