Sparta won the Peloponnesian War by decisively crushing the Athenian navy at the battle of Aegospotami in 405 BC. Earlier in the war, Sparta had inflicted a severe naval defeat on Athens at the battle of Syracuse in 413 BC. The ability to defeat Athens at sea came from Persian funding which permitted Sparta to build a fleet of two hundred triremes. Otherwise, the Spartan navy would have been outmatched by the Athenians. The victory put an end to the decades-long war between the two rival powers and their allies; the on and off fighting had spanned the region on land and on sea since 460 BC.

Military background

Sparta’s hoplite army was the preeminent land force in fifth century Greece. Due to their rigorous training and specialization, Spartan hoplites were second to none. As a unit, known as the phalanx, the Spartan hoplites were more effective than the other greek phalanxes by a considerable margin. In previous wars, against both the Persians and neighboring Greek city-states, Sparta had proved that its warriors were the elite on land. Their martial reputation was well-established by battles such as Thermopylae in 480 BCE.

Athens was also a leading military power of the period, but of a different sort. The Athenian navy, based out of the port of Piraeus, had played a leading role in the defeat of the Persian naval forces at the battle of Salamis in 480 BC. While the Persian navy had been smashed at Salamis (putting an end to their land campaign as well), the victory had been hard-won for the Athenians in particular. They had to evacuate their city and watch as the Persian armies sacked and burned it. The experience taught them an important military lesson: their power at sea was substantial, but it had only given them limited options against land-based threats to the city itself. And so Athens came up with a brilliant strategic solution, which raised eyebrows across the Aegean and beyond. A long wall was built which encompassed both the city of Athens and the harbor of Piraeus, including the land corridor between them. It was an enormous fortification for that period. The concept permitted:

  1. A defense of the city from siege and land attack
  2. A defense of the port from land attack which meant safe harbor for the navy
  3. Resupply of Athens from the sea even whilst under siege
  4. Manpower and communication to flow freely between the city and its navy

The Athenian hoplites and phalanx, while not on par with the Spartans, were certainly not to be dismissed. Athens had led the Greeks to victory at Marathon in 490 BCE and had fought alongside the Spartans at Plataea in 479 BC (see the Persian War). Athens had a long martial record, including wars with its neighbor Thebes with which it competed for power over the Boeotian region.


The respective alliances of Sparta and Athens during the Peloponnesian war, reflected their spheres of geographic and military dominance. Sparta led the Peloponnesian League which was an alliance of neighboring cities such as Elis, Tegea and Mantinea, and the League was also joined by Athens’ maritime rival – Corinth. Under the alliance, Sparta would lead the troops of all the cities in war – a unified army under Spartiate control. The junior allies undertook that the allies and enemies of Sparta would be their allies and enemies too.

For its part, Athens led an alliance which reflected its maritime power. With over three hundred members, the Delian League was an alliance with a strong naval component. Many of the Greek island states were members, including Chios, Lesbos, Samos and Nexos. Indeed membership spanned the whole of the Aegean Sea from the Hellespont to the Cyclades. Initially the alliance had a democratic element to it with each state paying tribute or supplying ships toward the alliance, and presumably having a say in the decision-making. Early on, the League treasury was located on the island of Delos. The fleet was led by Athens whose position in the alliance grew to greater and greater dominance over the other members. Eventually the alliance’s funds were moved to Athens, and the League became a de facto Athenian empire. This became clear when some members wanted to leave the alliance and were either invaded, or besieged by Athens until they submitted to the latter’s political will.


Both the Delian and Peloponnesian Leagues adopted strategies that played to their strengths. In the course of the war, Sparta repeatedly invaded Attica to destroy the farmland which surrounded Athens, and it attempted to lay siege to Athens, repeatedly and unsuccessfully. The Athenians wisely chose not to go into the field against Spartans, and they remained behind their long wall, watching the landscape burn. Instead, Athens used its fleet to blockade and to raid the Peloponnese; landing by ship, the Delian warriors had the element of surprise and could escape before local garrisons had time to respond. Eventually, Athens gained a foothold in the Peloponnese at Pylos. In a naval engagement at Sphacteria, the Spartan navy was destroyed and its hoplites, isolated on an island, unexpectedly submitted their surrender. Successful as the Delian navy was, it was never able to threaten Sparta itself.

The fortunes of war swung both ways. Besieged Athens suffered a devastating attack of the plague and its citizenry was decimated. Pericles, one of the Athenian leaders, succumbed to the disease.

Unable to defeat each other in direct confrontation, Sparta and Athens were at a stalemate for long periods of the war and resorted to targeting each others allies. Each side attempted to isolate the other strategically in this manner. Unlike the single-day hoplite battles of past wars between the Greeks, the Peloponnesian war developed into total war. Atrocities against civilians and whole scale slaughter were committed by both sides against rival communities, as the armies themselves seldom met in pitched battle. The employment of mercenaries for raids was common and the policy likely contributed to the ravaging. Political subterfuges and the incitement of rebellions were used to subvert the opponents allies.

In this brutal game of chess, Sparta began to make some advances. In 424 BC, a Spartan army led by Brasidas crossed north through Attica and into Thrace. The roving Spartan army laid bare the inability of Athens to defend its Delian League allies on the mainland. The campaign underlined this point emphatically when Amphipolis, itself an Athenian colony, fell to the Spartans.

Athens tried a similar strategy by using the League’s navy to subjugate neutral island-states in the Aegean Sea, and strike at or subvert Peloponnesian and overseas allies of the Spartans. One success was an alliance the Athenians made with Elis, Argos and Mantinea which threatened Sparta in the Peloponnese.  The alliance was however defeated by Sparta in one of the few pitched battles of the war.  A few years later, an overseas campaign went badly for Athens. When the Delian League attempted an invasion of Syracuse, a Corinthian ally, in Sicily in 415-413 BC; it lost 40,000 men and its fleet there in a mismanaged campaign.  Athenian naval dominance was severely diminished.

The Endgame

With the naval capability of the Delian League largely reduced, and the continued dominance of Spartan forces on land, Delian League members began to defect. Sparta moved to place a choke grip on Attica by occupying it on a permanent basis. A garrison of Spartans were stationed at Decelea from 413 BC onwards, and Athens became increasingly isolated militarily and politically. Critically for Sparta, the Persians began to finance the Peloponnesian fleet as they properly viewed the Delian League to be a threat to Persian interests in Ionia. As the fleet steadily grew it began to match and then outnumber the Athenian fleet and the latter was forced on the defensive even in the Aegean.

The final event that broke the power of Athens came at the battle of Aegospotami in 405 BC. A Spartan fleet under the command of Lysander had sailed to block the Athenian supply of grain from the Black Sea. An Athenian fleet moved quickly to prevent this and met Lysander in the Hellespont. Even though they had come to fight, the Athenians were caught disorganized and unprepared one day and the Athenian navy was almost totally annihilated by the Spartans. In 404 BC, the Spartans took a near-defenceless Piraeus and Athens, and brought down the famous long wall between them.

The Aftermath

Athens was starved, its forces destroyed and the city bankrupt. The Delian League was dissolved and Sparta replaced the democracy of Athens with an oligarchical puppet regime known as The Thirty Tyrants. For its part, victorious Sparta was now the supreme city-state and was poised to dominate the region. In the decades that followed, a brief Spartan empire would control southern Greece and much of the Aegean Sea.

However, the war had brought many changes not all to the Spartans benefit. Warfare in Greece had changed dramatically from standard hoplite vs hoplite one-day battles to brutal total war where few rules were honored. This did not bode well for Sparta which was itself so reliant on its upper hand in traditional phalanx warfare. The end of the long-held Athens-Sparta rivalry brought unforeseen changes to the Greek political landscape. The power of Thebes, which had often been checked by that of Athens, now began a more unfettered ascent, and it would grow to rival Sparta.

The extent of Spartan power at the end of the Peloponnesian War


Further Reading:


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