once the ionian revolt was crushed by the persian victory at the battle of lade, darius began planning to conquer greece. in 490 bc, he sent a naval task force under datis and artaphernes across the aegean, to subjugate the cyclades, the group of greek islands in the aegean sea. the next step was to attack athens and eretria. after a successful campaign in the aegean, the persians defeated, captured and burnt eretria. "/