Peloponnesian War and Thucydides

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  1. 0:05 The Historic Account of Thucydides
  2. 1:21 Causes of the War
  3. 4:24 Pericles' Grand Strategy
  4. 6:18 Pericles' Plan Falls Apart
  5. 11:32 Lesson Summary
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Taught by

Max Pfingsten

This lecture covers the Peloponnesian War. First we enumerate the causes of the war. Then we examine Pericles' plan to win it. We see how Pericles' plan eventually fell apart and how the Athenians struggled without leadership until their eventual destruction at the hands of the Spartans.

The Historic Account of Thucydides

Pretty much everything I know about the Peloponnesian War I learned from Thucydides.

Thucydides was a wealthy fellow from the suburbs of Athens. He served as a general in the Peloponnesian War and actually managed to survive the whole bloody affair. Thucydides' History of the Peloponnesian War is no memoir, though. In its day, it was the most thorough historical account ever written. And, in my humble opinion, we haven't made many improvements since then. Thucydides has all the qualities that have come to define a great historian. He's unbiased (or at least trying to be). He's incredibly thorough. He's not interested in the supernatural, only the rational. And, best of all, he was there. So, much as I would like to tell you about the Peloponnesian War, the honor belongs to my good friend Thucydides.

Megara formed an alliance with Athens in its fighting with Corinth
Megara Corinth Map

The Peloponnesian War was a chaotic, messy conflict between Athens and Sparta that dragged on for nearly 30 years. At the beginning of the war, Athens controlled a vast maritime empire. By the end of the war, Athens had been stripped of its empire and did not even control itself. So what happened to bring the mighty Athenian empire low?

Causes of the War

The causes of the Peloponnesian War stretch back for decades. After the Persian navy was destroyed at the battle of Mycale, the Athenians founded the Delian League to punish the Persians by taking their colonies in the Aegean and adding them to the Athenian Empire. With no navy to defend them, the Persians were soundly defeated, and within 30 years, the Athenians controlled a vast maritime empire containing most of the islands in the Aegean and much of the coast of Asia Minor. Meanwhile, back at home, as Athens grew ever richer and more powerful, the Spartans were feeling increasingly nervous about Athens' imperial ambitions. As I wrote in my history, 'The growth of the power of Athens, and the alarm which this inspired in Lacedaemon (Sparta), made war inevitable.'

Sparta had its own league, the Peloponnesian League, which included most of the city-states of mainland Greece, and they did not appreciate the Athenians trying to poach their member states for their Delian League. In 465 BCE, Sparta's slave class, the Helots, attempted to throw off their Spartan oppressors. Every Greek city-state sent soldiers to help put down the revolt. The Athenians sent a large contingent of over 5,000 soldiers, but the Spartans would not allow them into the country, fearing that so large a force intended to take advantage of the chaos, not to help with it. This was but the first of many insults each side offered each other. The next major insult came in 449, when two members of the Peloponnesian League, Megara and Corinth, started fighting. Eager to gain a stronghold on the mainland, Athens formed an alliance with Megara and entered the fighting. The result was a 15-year-long struggle between Athenians and Spartans, which some have called the First Peloponnesian War. This battle only concluded in 445 BCE with the signing of the 30 Years' Peace. The 30 Years' Peace was basically an agreement between the Spartans and the Athenians not to mess with one another's respective empires. Yet the terms of this peace proved too much for the Athenians to live by.

For the next 15 years, Athens starting acting more and more like a bully. They crushed revolting colonies, they sowed dissent among Sparta's allies, they vied with their neighbor, Corinth, for control of the islands of the Aegean and they even imposed economic sanctions on their former allies the Megarians - until, in 431, the rest of the world could take it no longer. Athens had made enemies of the Spartans, the Peloponnesian League, the King of Macedon, the emperor of Persia and even their own allies. Everyone was so mad at Athens that a conflict was inevitable. But the Athenians were prepared for this fight.

The Athenian leader Pericles

Pericles' Grand Strategy

Their leader, Pericles, had been certain that the 30 Years' Peace would not live up to its name. So as soon as the Spartans had left the land surrounding Athens, they had started building a long wall connecting the city of Athens to its port, Piraeus. In this way, Pericles said, Athens could behave like an island. It did not matter that the Spartan army was invincible. Athens never had to meet Sparta on land. It did not matter if Sparta burned their fields and stole their flocks. Athens had an entire empire to import food from. As long as the Athenian navy reigned supreme, it could keep the city supplied against even the longest siege.

Moreover, that navy allowed the Athenians another advantage over their land-based foes the Spartans. An army is only useful in a battle. It spends most of its time moving from point A to point B. This might take months. As a result, that amazing Spartan army was really only useful for a few days out of the month. By contrast, with their ships, the relatively small Athenian army could show up anywhere at any time. They could disembark, do their damage and beat back to sea before their enemies could muster any resistance. The speed and mobility of the Athenian navy was especially dangerous to Sparta since their slaves, the Helots, were always on the brink of revolt. The Spartans had to keep much of their army at home at all times lest the Athenians sail around them and stir up a revolt in their homeland. So, despite being surrounded by enemies, it seemed the Athenians were in an excellent position. They could hold their empire, Pericles warned, so long as they did not try to expand upon it. Yet there were things that Pericles did not account for.

Pericles' Plan Falls Apart

The first and foremost of these was that when you shove thousands of people within city walls for months with no room and only primitive forms of sanitation, people tend to die. The walls protected the Athenians from the Spartans, but the tight quarters made them prone to disease. Within the first year of the war, a plague swept through the city of Athens, killing over 30,000 Athenians. It was a dreadful affair, not the least because the plague took Pericles, the visionary who'd turned Athens into an empire. Without their leader, the democratic Athenians found it impossible to prosecute the war effectively. They had no single mind, no single vision to unite them. Instead, Athenian strategy vacillated from aggressive to defensive as different demagogues rose to power and fell from grace.

Hold on, Thucydides, I'm not sure our viewers know what a demagogue is.

Oh, really? Kids these days. A demagogue is a leader who follows the people instead of leading them. He tells them what they want to hear and simply tries to keep them happy so he'll get re-elected.

Really? We call those politicians.

The long wall allowed Athens to function as an island
Athens Wall Map

What a horrible world you must live in. Anyway, Pericles wasn't like that. He taught the people. He reasoned with them. He encouraged them to reach their full potential. The demagogues just rode the wind of whatever the mob drove them to. The worst of these demagogues was Alcibiades. Alcibiades was everything the Athenians were looking for. He was rich. He was sexy. He was even relatively clever, having studied under Socrates. Alcibiades could work up a crowd like a pro. Yet none of these characteristics made him trustworthy. Alcibiades encouraged the Athenians to abandon Pericles' excellent plan to not expand the empire. Instead, Alcibiades suggested an ambitious campaign to Sicily, which was struggling to fight off an invasion from Syracuse. Alcibiades led the expedition himself. Yet when the Athenians recalled him, he defected to the Spartans and betrayed all of Athens' plans. This would not be his last defection. Alcibiades switched teams several times in the course of the war, from the Spartans to the Athenians and then back again. He even worked for Persia for a while. The Persians were all too eager to help Greeks kill other Greeks, and the worldly Alcibiades acted as an intermediary. Eventually, his dupes lost their fondness for him and killed Alcibiades for his treachery.

Yet Alcibiades was but one of a long list of ambitious men who sought to lead Athens. Any one of these leaders' plans might have worked, but the constantly shifting Athenian war policy doomed every effort. Without a firm hand to guide them, the Athenian populace made blunder after blunder. They switched commanders on a dime, yet held to disastrous strategies year after year. When the first expedition to Sicily failed, they sent another, and then another, until nearly the entire Athenian fleet had been destroyed and most of the Athenian navy had been sold into slavery. Despite these catastrophes, the Athenians struggled on for another decade. They raised new armies and built new ships. Yet their continued naval supremacy was mostly due to the genius of their commanders. Unfortunately, in a fit of rashness, in 406 BCE the Athenians executed their greatest naval commanders after the battle of Arginusae. Though the battle was a great victory, the generals had retreated to save their fleet from a storm instead of remaining behind to collect stranded soldiers and finish off the Spartan fleet. For this, they were sentenced to death. With no decent leaders left, the Athenians blundered hopelessly. In 405 BCE, their last fleet was destroyed by a Spartan force sailing in Persian ships, and the following year Athens surrendered.

The Spartans tore down the walls of Athens, disbanded its democracy and set up an oligarchy, the Thirty Tyrants. This group killed off many of the most prominent men of Athens. Yet Sparta's victory was short-lived. Within a year, the Athenians had expelled the tyrants and re-established their democracy. Yet the damage had been done. The two greatest powers of Greece had weakened one another to such an extent that neither would ever fully recover. Over the following decades, Athens and Sparta had to bend knee, first to their fellow Greeks, the Thebans and then to the invading Macedonians.

Alcibiades was the worst of the Athenian demagogues

Lesson Summary

Thanks, Thucydides. That was awesome and quite thorough. To summarize, the Peloponnesian War was fought between Athens and Sparta. Both of these city-states were the heads of large leagues of allied cities. Athens' Delian League controlled the sea with a powerful navy. Sparta's Peloponnesian League controlled the mainland of Greece with a powerful army. Athens' steady rise in power and wealth caused anger among the Spartans and even among its own allies. When war finally broke out, the Athenian leader, Pericles, suggested that Athens behave like an island. They should not try to meet the Spartans in open battle but should stay inside the city. An unforeseen result of these close quarters was a plague that killed off much of the Athenian population, including Pericles.

After losing Pericles to the plague, the Athenians made a series of grave strategic errors, including a drawn-out expedition to Sicily and the condemnation of some of their greatest leaders to death. These mistakes, and Athens' general inability to stick to a course of action without a central leader to guide them, ended up costing the Athenians their empire.

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