The Mytilenean revolt was an incident in the Peloponnesian War in which the city of Mytilene attempted to unify the island of Lesbos under its control and revolt from the Athenian Empire. In 428 BC, the Mytilenean government planned a rebellion in concert with Sparta, Boeotia, and certain other cities on the island, and began preparing to revolt by fortifying the city and laying in supplies for a prolonged war. These preparations were interrupted by the Athenian fleet, which had been notified of the plot, and the Mytileneans sent representatives to Athens to discuss a settlement, but simultaneously dispatched a secret embassy to Sparta to request support.