A small detachment of Spartans under Leonidas had been told to guard the narrow road between the high mountains and the sea which connected Thessaly with the southern provinces. Leonidas obeyed his orders. He fought and held the pass with unequalled bravery. But a traitor by the name of Ephialtes who knew the little byways of Malis guided a regiment of Persians through the hills and made it possible for them to attack Leonidas in the rear. Near the Warm Wells--the Thermopylae--a terrible battle was fought. When night came Leonidas and his faithful soldiers lay dead under the corpses of their enemies. But the pass had been lost and the greater part of Greece fell into the hands of the Persians. They marched upon Athens, threw the garrison from the rocks of the Acropolis and burned the city. The people fled to the Island of Salamis. All seemed lost. But on the 20th of September of the year 480 Themistocles forced the Persian fleet to give battle within the narrow straits which separated the Island of Salamis from the mainland and within a few hours he destroyed three quarters of the Persian ships. In this way the victory of Thermopylae came to naught. Xerxes was forced to retire. The next year, so he decreed, would bring a final decision. He took his troops to Thessaly and there he waited for spring. But this time the Spartans understood the seriousness of the hour. They left the safe shelter of the wall which they had built across the isthmus of Corinth and under the leadership of Pausanias they marched against Mardonius the Persian general. The united Greeks (some one hundred thousand men from a dozen different cities) attacked the three hundred thou-sand men of the enemy near Plataea. Once more the heavy Greek infantry broke through the Persian barrage of arrows. The Persians were defeated, as they had been at Marathon, and this time they left for good. By a strange coincidence, the same day that the Greek armies won their victory near Plataea, the Athenian ships destroyed the enemy's fleet near Cape Mycale in Asia Minor. Thus did the first encounter between Asia and Europe end. Athens had covered herself with glory and Sparta had fought bravely and well. If these two cities had been able to come to an agreement, if they had been willing to forget their little jealousies, they might have become the leaders of a strong and united Hellas. But alas, they allowed the hour of victory and enthusiasm to slip by, and the same opportunity never returned. ATHENS vs. SPARTA HOW ATHENS AND SPARTA FOUGHT A LONG AND DISASTROUS WAR FOR THE LEADERSHIP OF GREECE