History of the Peloponnesian War

So they went forth with their children and their wives, and being received by Athens from the hatred that she now felt for the Lacedaemonians, were located at Naupactus, which she had lately taken from the Ozolian Locrians.

The Athenians received another addition to their confederacy in the Megarians; who left the Lacedaemonian alliance, annoyed by a war about boundaries forced on them by Corinth. The Athenians occupied Megara and Pegae, and built the Megarians their long walls from the city to Nisaea, in which they placed an Athenian garrison. This was the principal cause of the Corinthians conceiving such a deadly hatred against Athens.