Angered by their defeat at the Battle of Marathon, the Persians, under their new king, Xerxes I, were determined to subjugate Greece. Greece comprised a series of city-states, with Athens and Sparta the most powerful. In spring 480 BCE the Persians launched a combined land and sea invasion. The Persian army marched south through Macedon, while their fleet travelled through the Athos canal and along the coast of Thessaly and Euboea. The Persian advance was delayed by seven days, when a small army of Spartans blocked their path at Thermopylae. Meanwhile, the Persian navy was detained for three days at Artemisium by the Greek fleet, where both sides suffered considerable losses. The Greeks, after hearing of their losses at Thermopylae, withdrew to Salamis, a small island close to Athens. The Persians overran Thebes and Plataea before they captured Athens, whose citizens had evacuated on ships to Salamis.
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