Sicilian Expedition

Part of the Peloponnesian War

Date	415–413 BC
Location	Sicily
Result	Decisive Athenian defeat, complete destruction of the Athenian expeditionary force

Belligerents

Athens, allies from the Delian League, Segesta

Syracuse, Corinth, Sparta

Commanders and leaders

Nicias (POW)

,
Lamachus †,
Demosthenes (POW)

,
Eurymedon †

Gylippus,
Hermocrates

Strength

Original Expedition: 5,100 hoplites, 750 Mantineans and Argives, 1,300 light and missile troops, 30 cavalry
134 triremes
Reinforcements: 5,000 hoplites, large number of light troops, 73 triremes

unknown, but included at least 1,200 cavalry and 1,000 Spartans
at least 100 ships

Casualties and losses

Entire expeditionary force killed, captured or sold into slavery

unknown

Alcibiades began the conflict as one of the Athenian commanders, but was recalled to Athens to face trial and subsequently defected to Sparta

The Sicilian Expedition was an Athenian military expedition to Sicily, which took place during the period from 415 BC to 413 BC (during the Peloponnesian War). The expedition was hampered from the outset by uncertainty in its purpose and command structure—political maneuvering in Athens swelled a lightweight force of twenty ships into a massive armada, and the expedition's primary proponent, Alcibiades, was recalled from command to stand trial before the fleet even reached Sicily—but still achieved early successes. Syracuse, the most powerful state on Sicily, responded exceptionally slowly to the Athenian threat and, as a result, was almost completely invested before the arrival of a Spartan general, Gylippus, galvanized its inhabitants into action. From that point forward, however, as the Athenians ceded the initiative to their newly energized opponents, the tide of the conflict shifted. A massive reinforcing armada from Athens briefly gave the Athenians the upper hand once more, but a disastrous failed assault on a strategic high point and several crippling naval defeats damaged the besiegers' fighting capacity and morale, and the Athenians were eventually forced to attempt a desperate overland escape from the city they had hoped to conquer. That last measure, too, failed, and nearly the entire expedition surrendered or was destroyed in the Sicilian interior.

The impact of the defeat was immense. Two hundred ships and thousands of soldiers, an appreciable portion of the city's total manpower, were lost in a single stroke. Athens's enemies on the mainland and in Persia were encouraged to take action, and rebellions broke out in the Aegean. The defeat proved to be the turning point in the Peloponnesian War, though Athens struggled on for another decade. Thucydides observed that contemporary Greeks were shocked not that Athens eventually fell after the defeat, but rather that it fought on for as long as it did, so devastating were the losses suffered.

Although Athens had never involved itself deeply in Sicilian affairs, it had ties there before the onset of the Peloponnesian War, dating back to at least the mid-5th century BC. To small Sicilian cities, Athens was a potential counter to the powerful city of Syracuse, which was strong enough to potentially dominate the island. (Syracuse, like Sparta and its Peloponnesian allies, was a Dorian city, while most of Athens's allies on the island were Ionian.) To the Athenians, Sicily was a threat—an unencumbered Syracuse might send grain or other aid to the Peloponnesians—as well as a venue for possible conquests.

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Wikipedia