What Happened During the Peloponnesian War in Ancient Greece?

The Peloponnesian War, fought between Athens and Sparta from 431 to 404 BCE, was one of the most significant conflicts in ancient Greece. This war had a profound impact on the development of Greek history and culture. Let’s dive into the details of what happened during this tumultuous period.

The Causes of the War

The main cause of the Peloponnesian War was the growing tension between Athens and Sparta, two powerful city-states with vastly different political systems. Athens, known for its democratic government and naval dominance, aimed to expand its empire and influence over other Greek city-states. On the other hand, Sparta, a militaristic society focused on land power, perceived this as a threat to their own supremacy.

The Outbreak of Hostilities

In 431 BCE, the war began when open conflict erupted between Athens and Sparta. The Athenians took advantage of their powerful navy by blockading the Spartan coast and raiding their territories. The Spartans responded by invading Attica, the region surrounding Athens.

The Archidamian War (431-421 BCE)

During this initial phase of the war, named after Spartan King Archidamus II, Athens faced numerous setbacks. The devastating plague outbreak in 430 BCE severely weakened their population and military forces. However, under the leadership of Pericles, Athens managed to hold out against Spartan advances.

As time passed, both sides sought allies to strengthen their positions. Athens formed an alliance called the Delian League with other city-states that opposed Sparta. Meanwhile, Sparta created its own coalition known as the Peloponnesian League.

The Peace of Nicias (421-413 BCE)

In 421 BCE, a temporary peace agreement was reached between Athens and Sparta under Nicias’ leadership. This peace allowed both sides to recover and rebuild their forces. Unfortunately, this period of relative calm didn’t last long.

In 415 BCE, Athens launched a disastrous expedition to conquer Syracuse, a powerful city-state in Sicily. The Athenians suffered a crushing defeat, losing many of their soldiers and ships. This defeat significantly weakened Athens and emboldened Sparta.

The Decelean War (413-404 BCE)

After their victory in Syracuse, Sparta gained the upper hand and intensified its efforts to topple Athens. They occupied the city of Decelea, which cut off Athens’ main source of grain from the Black Sea.

The Spartans also received support from Persia, who sought revenge against Athens for their previous interference in Persian affairs. With Persian funding, Sparta built a formidable navy that challenged Athens’ maritime superiority.

The End of the War

By 404 BCE, after years of brutal conflict and numerous sieges, Athens finally surrendered to Sparta. The victorious Spartans dismantled the Athenian democracy and installed an oligarchic regime known as the Thirty Tyrants.


The Peloponnesian War had profound consequences for ancient Greece. It weakened both Athens and Sparta, leaving them vulnerable to future conquest by other powers such as Macedon led by Philip II and his son Alexander the Great.

Furthermore, this war shattered the sense of unity among Greek city-states and highlighted the destructive nature of internal conflicts. It marked the end of the golden age of Athens’ cultural achievements under Pericles’ leadership.

  • It is worth noting that Thucydides provided an invaluable account of this war in his famous historical work ‘History of the Peloponnesian War.’
  • The Peloponnesian War serves as a cautionary tale about how rivalries between powerful states can lead to devastating consequences.

In conclusion, the Peloponnesian War was a pivotal event in ancient Greek history. It showcased the clash between two dominant city-states, Athens and Sparta, and its repercussions shaped the course of Greek civilization for centuries to come.