Background. In 499 B.C.E. the Ionian Greeks, those residing on the coast of Asia Minor and various islands in the Aegean Sea, rebelled against their Persian overlords. Some of the Greek city-states were sympathetic to the plight of the rebels during these early Persian Wars, and Athens and Eretria sent military aid in the form of warships. Nevertheless, the Persian king Darius I crushed the rebellion by 494 and then decided to chastise the interfering Greek city-states. In the case of the Athenians, he wished to reimpose on them the rule of the tyrant Hippias, who had been forced from Athens twenty-one years before. In the summer of 490 B.C.E. a Persian army of approximately 26,000 men landed in Greece; while one-half of the force laid siege to Eritrea on the island of Euboea, the remainder bivouacked twenty-six miles...