CAUSES OF THE FIRST WAR.
The various successful schemes of Pericles for enriching and extending the power of Athens were regarded with fear and jealousy by Sparta and her allies, who were only waiting for a reasonable excuse to renew hostilities. The opportunity came in 435 B.C. Corinth, the ally of Sparta, had become involved in a war with Corcy'ra, one of her colonies, when the latter applied to Athens for assistance. Pericles persuaded the Athenians to grant the assistance, and a small fleet was dispatched to Corcyra. The engagement that ensued, in which the Athenian ships bore a part —the greatest contest, Thucydides observes, that had taken place between Greeks to that day—was favorable to the Corinthians; but the sight of a larger Athenian squadron advancing toward the scene of action caused the Corinthians to retreat. This first breach of the truce was soon followed by another. Potidæ'a, a Corinthian colony, but tributary to Athens, revolted, on account of some unjust demands that the Athenians had enforced against it, and claimed and obtained the assistance of the Corinthians. Thus, in two instances, were Athens and Corinth, though nominally at peace, brought into conflict as open enemies.