From thenceforth there was almost a constant warfare between the political parties or factions of the republic, while jealous eyes outside were consequently watching an opportunity for its destruction. Ambitious demagogues were constantly using the people as their tools, but scarcely would one obtain the chief magistracy until another would pull him down--if not by a vote of the people, then by faction or by assassination. Meanwhile Hippias, who had been dethroned, sought aid from the king of Persia to reinstate him, and thus brought a long and bloody war upon his own country. In this war were fought the renowned battles of Marathon, Salamis, Plateæ, and Mycale, and the Greeks came off victorious, but at a most fearful sacrifice of treasure and life. After this followed the disunion among the several Grecian states--the secession of some--the coldness and indifference of others; and though the brilliant administrations of Cimon and Pericles seemed to revive the republic for awhile, it was evident to all that the seeds of death were fast germinating and would bring forth fruit erelong. The Persian king, and the sovereigns of other surrounding countries, had long felt deep jealousy of the Athenian Republic, and, when an excuse came for attacking it, they were not backward in availing themselves of the opportunity. Fortunately for the Athenian Republic the attack made upon them by Persia had the effect to bring the whole power of the Spartan Republic to their aid, which, with such other aid as they received from minor states of Greece, enabled them to defeat the Persians in the end and maintain their own independence.