In 412 B.C., when the Peloponnesian War had reached its most critical stage for Athens after her Sicilian losses, Chios and Erythrae revolted from the Athenian League and appealed to Sparta for armed assistance. This was sent, despite Athenian attempts at interception, and the revolt spread up and down the Asia Minor coast. The Athenians reacted quickly, sent ships to Samos, recaptured Lesbos, and opened operations against Chios by raiding the countryside near Chios town. A hostile Chios with her war fleet constituted the major threat to Athenian interests in the East, and stronger measures, which might also provide more permanent security, were needed. Thucydides tells (viii. 38, 2) how the Athenian ships ‘crossed from Lesbos to Chios with armed force, and, in command of land and sea, fortified Delphinion, a place strong on the landward side, served by harbours, and not far distant from Chios town’.