Sicilian Campaign (413 B.C.)Sicilian Campaign (413 B.C.) - The Athenian expedition which more or less sealed Sparta's victory in the Peloponnesian War.  Syracuse, the largest city-state on the island of Sicily and originally a Corinthian colony, was allied with Sparta during the war.  The expedition was the brainchild of Alcibiades, a young Athenian aristocrat and general.  Opposed to it was another general named Nicias, who ironically ended up leading it after Alcibiades fled Athens under a cloud of scandal.  The expedition ended in disaster when the fleet was destroyed by an equally powerful Syracusan fleet.