Introduction: The Dramatic Final Act

Welcome to the final chapter of our Greek period study! If the Peloponnesian War were a movie, this would be the high-stakes finale. In the previous chapter, the Peace of Nicias (421 BC) was supposed to end the fighting, but it was more of a "cold war" than a real peace. In these final years (419–404 BC), we see Athens take its biggest risks, suffer its greatest losses, and ultimately face a total collapse. We will look at how alliances shifted, the disastrous gamble in Sicily, and how the intervention of Persia finally tipped the scales in favor of Sparta.

1. The Alliance of Athens, Argos, Mantinea, and Elis (419–418 BC)

Even though Athens and Sparta were technically at peace, Athens began looking for ways to weaken Sparta's control over the Peloponnese. Led by the ambitious young general Alcibiades, Athens formed a new "Quadruple Alliance" with Argos, Mantinea, and Elis.

Why was this important?
Argos was Sparta’s traditional rival in the Peloponnese. By siding with them, Athens was "poking the lion" in its own backyard. This led directly to the Battle of Mantinea (418 BC).

The Battle of Mantinea (418 BC):
This was the largest land battle of the war. Sparta won a decisive victory. Key Takeaway: Before this battle, many Greeks thought Sparta had lost its "invincible" reputation after their defeat at Pylos. Mantinea restored Spartan prestige and secured their control over the Peloponnese. Athens had failed to break Sparta's land power.

2. The Sicilian Expedition (415–413 BC)

This is often seen as the turning point of the entire war. Athens decided to send a massive fleet to Sicily, officially to help an ally (Segesta), but really to conquer the wealthy city of Syracuse and expand their empire.

The Decision to Go

According to Thucydides, there was a huge debate in the Athenian Assembly. Nicias (the cautious general) argued it was too risky and expensive. Alcibiades (the flamboyant risk-taker) argued that Athens must keep expanding to survive. The Athenians were so excited by the prospect of wealth that they voted for an even bigger expedition than originally planned!

The Disaster at Syracuse

Things went wrong almost immediately. Alcibiades was recalled to Athens to face trial for religious crimes (the Mutilation of the Hermae), so he defected to Sparta and told them exactly how to defeat Athens!
The expedition ended in a total catastrophe:

  • The Athenians failed to blockade Syracuse.
  • Sparta sent a general named Gylippus who helped organize the Syracusan defense.
  • The Athenian fleet was trapped in the Great Harbour of Syracuse and destroyed.
  • Thousands of Athenian soldiers were killed or forced to work as slaves in stone quarries.

Key Takeaway: Thucydides famously wrote that the Athenians were destroyed "fleet and army and everything." Athens lost its best ships, its best soldiers, and its financial reserves. This is a primary reason for "Athenian failure" in your historical debates.

3. The Decelean War and the Occupation of Decelea (413 BC)

While Athens was losing in Sicily, they were also losing at home. On the advice of the traitor Alcibiades, the Spartans changed their strategy. Instead of just invading Attica every summer and then leaving, they built a permanent fort at Decelea.

Impact of the occupation:

  • Economic Ruin: Athenians could no longer farm their land year-round.
  • Slave Escapes: Over \(20,000\) slaves (mostly skilled miners) escaped to the Spartan side.
  • Supply Lines: Athens became completely dependent on imported grain from the Black Sea.

4. The Persian Factor (Relations with Non-Greek States)

This is a crucial part of your syllabus! For most of the war, Persia watched from the sidelines. After the Sicilian disaster, Persia saw an opportunity to win back the Greek cities in Ionia (modern-day Turkey) that Athens had controlled.

The Deal with the Devil

Between 412 and 411 BC, Sparta and Persia signed a series of treaties. The Trade-off: Persia would provide the gold Sparta needed to build a massive fleet. In return, Sparta would allow Persia to take back control of the Ionian Greeks. Key Figures: Tissaphernes and Pharnabazus (Persian Satraps/Governors) played the Greeks against each other. Later, Cyrus the Younger (the Persian King’s son) gave full support to the Spartan general Lysander.

Did you know? Without Persian money, Sparta could never have challenged Athens at sea. Athens’ only advantage was its navy, and Persia effectively bought Sparta a winning fleet.

5. The Final Collapse (405–404 BC)

With Persian funding and the leadership of Lysander, the Spartan navy finally cornered the Athenians.

The Battle of Aegospotami (405 BC)

Lysander caught the Athenian fleet off-guard at the Hellespont (a vital shipping lane). He captured almost the entire fleet without a fight. This was the "checkmate" move because it cut off the Athenian grain supply from the Black Sea.

The Surrender (404 BC)

Starving and without a navy, Athens surrendered. The Terms of Peace:

  • The Long Walls and the fortifications of Piraeus were torn down (to the sound of flute-music, according to Xenophon).
  • Athens lost all its overseas empire.
  • Athens was forced to become an ally of Sparta, following Sparta's lead in war and peace.

Quick Review: Why did Athens lose?

When you are preparing for your Historical Debates essay, remember these three key factors from this chapter:

  1. Strategic Blunders: The Sicilian Expedition was a massive waste of resources.
  2. The Spartan Fort at Decelea: This put constant economic pressure on Athens.
  3. The Persian Intervention: Persian gold allowed Sparta to build a navy that could finally match Athens.

Common Mistake to Avoid: Don't assume Athens was "weak" immediately after Sicily. They actually rebuilt their fleet and won several battles (like Arginusae in 406 BC). Their failure was a gradual process of exhaustion and the overwhelming combination of Spartan grit and Persian money.

Key Takeaways

- The Battle of Mantinea (418 BC) restored Spartan dominance in the Peloponnese.
- The Sicilian Expedition (415-413 BC) was a catastrophic military and financial failure for Athens.
- The occupation of Decelea crippled the Athenian economy.
- Persian gold was the decisive factor that allowed Sparta to win the naval war.
- Aegospotami (405 BC) led to the total surrender of Athens in 404 BC, ending the Golden Age of the Athenian Empire.