The Sicilian Expedition: Facts & Significance

Instructor: Christopher Muscato

Chris has a master's degree in history and teaches at the University of Northern Colorado.

Not all military campaigns turn out to be good ideas. In this lesson, we'll explore the Sicilian Expedition, and see how it impacted the political relationships between the cities of ancient Greece.

The Sicilian Expedition and Peloponnesian War

When the Persians invaded Greece, the Greek city-states came together and fought for mutual survival. This was a great moment in Greek history, but that sort of cooperation was actually pretty rare. After the Persians were defeated, conflicts between the Greek cities thrust them into the Peloponnesian War. This Greek war pitted Athens against Sparta, and after numerous battles finally seemed to be over in 421 BCE.

Of course, like any Greek tragedy, the story doesn't end there. Toss in some pride, arrogance, and betrayal, and just like that, the war was back on. The tentative peace in 421 BCE was shattered in 415 BCE by an event known as the Sicilian Expedition.

The Peace of Nicias

The story of the Sicilian Expedition begins with the Peace of Nicias, which halted the war in 421 BCE. The Athenian general Nicias negotiated an exchange of prisoners and territories with Sparta, and set a truce that was meant to last for 50 years. Unfortunately, the treaty failed to fulfill the principle goals of either side, and the treaty was signed by leaders who intended to skirt it from the beginning.

As tensions began to boil over territories that hadn't been returned by either city, events in the Greek colonies of Sicily started to attract Athenian attention. The Athenian Ionian allies in Sicily were clashing against the Dorian people of Syracuse, an ally of Sparta. Athens' allies started asking for reinforcements to protect them against the growing Syracusan threat, and even went so far as to promise to pay for a new Athenian navy, greatly over-exaggerating their wealth.

The Athenians now had a decision to make. One faction, led by Nicias, argued fervently that Athenian intervention could be seen as an act of aggression. Nicias wanted to respect the peace.

The other side was led by Athenian general Alcibiades. Alcibiades and others saw this as a perfect opportunity to subtly strike back at the Spartans for failing to return some Athenian territories. It would also bolster the support of Athens' allies in Sicily, should Athens decide to try and claim some territory in the future. Allegedly, Nicias tried to argue against this by asking to build an even larger fleet than Alcibiades had, hoping to demonstrate the impossible nature of the plan. It backfired, and the Athenian government approved Alcibiades' plan, but now with Nicias' massive fleet.


The Expedition

Alcibiades' enthusiasm galvanized the Athenians, and they set to building a massive naval fleet. The expressed objective of the expedition was just to protect their allies, not start war, but the size of the fleet clearly indicated a preparedness for battle. In 415 BCE, the largest naval fleet in Athenian history left its harbors for Sicily.

The fleet was underway, but Alcibiades would not be in charge of it for long. His arrogance, lust for power and self-interest caught up with him. Just before the fleet was set to depart, somebody vandalized the Herms, a set of statues to Hermes guarding Athens that were supposed to protect the city. Alcibiades' political enemies blamed him for the sacrilegious vandalism, and he was recalled.

When the fleet arrived in Sicily, the city of Syracuse began to worry that this alliance was simply a ruse to attack them. As it turns out, they weren't wrong. The Athenian generals decided to reassure their allies by deciding to attack Syracuse right away. Syracuse was slow to bolster its defenses, and as a result it was almost conquered.

The Athenian fleet that attacked Syracuse was massive in size.

Sparta Arrives

The attack on Syracuse caught Sparta's attention, and they set out to defend their sister city. The Spartan response was also motivated by another factor: Alcibiades. Fearing that he would not receive a fair trial in Athens, Alcibiades defected and went to Sparta. There, the Athenian general informed the Spartans about the Athenian fleet, battle plans, and strategies.

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