How the Athenian Empire Caused Its Own Collapse

At its height, Athens controlled the entire Aegean Sea, yet several factors caused its empire to collapse in a mere 50 years.

May 14, 2024By Daniel Soulard, BA Classical Civilizations

athenian empire collapse


By the mid-5th century BCE, Athens controlled much of eastern mainland Greece, the Aegean islands, and the Ionic coast of Asia Minor. During this period, Athens flourished as the cultural hub of the Greek world and produced some of the most iconic artworks from antiquity. The power of Athens even worried the renowned Spartans, who famously slowed the advance of Persian forces at the pass of Thermopylae. But the stresses of empire proved too much, and mighty Athens collapsed under its own weight.


A League of Their Own

delian league peloponnesian allies map
Map showing the Delian League and Peloponnesian League before the Peloponnesian War, W.L. Westermann, 1912. Source: Wikimedia Commons


After the second Persian invasion of Greece, the allied Greek forces went on the offensive and liberated the Ionian cities along the coast of Asia Minor. The Spartans, who were the leaders of the Allied coalition, felt that the purpose of the war had been achieved and withdrew their forces. However, the Athenians stayed and vowed to protect the freed states from any further Persian aggression. The remaining Allies gathered on the island of Delos and formed a new alliance called the Delian League. Each member state was equal and decisions were made by vote. Their first order of business was to select a new leader of the league’s forces, and they chose Athens.


Membership in the league was beneficial, especially to smaller city-states. Building and maintaining a navy was costly, and the league provided a cheaper alternative since members who couldn’t provide ships could instead pay tribute. With by far the largest navy, Athens could provide enough protection on her own that many states opted to pay tribute. At first, the league was true to its purpose, freeing the remaining holdouts of Persian influence in the Aegean, but over time Athens revealed her imperialistic tendencies. “Liberated” cities were coerced into joining the league, and those who refused were colonized or put to the sword.


The Parthenon, Frederic Edwin Church, 1871. Source: The Metropolitan Museum of Art, New York


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Eventually, one member state,  the island of Naxos, attempted to leave the alliance. Athens’s response was quick and severe, laying siege to the city and enslaving its inhabitants. Over time, the inflow of funds and Athens’s growing experience in the field of war made it increasingly difficult for any to leave the league. This contributed to an air of fear that would come to define Athens’s reign of the Aegean. By 454 BCE, Athens lifted all pretense by moving the league’s treasury from the island of Delos to Athens itself, completing the transition from alliance to empire.


Empire of Democracy

iasos bouleuterion council house
Photograph of the bouleuterion at Iasos, Dick Osseman, 2007. Source: Wikimedia Commons


In 508 BCE the Athenian people installed a new form of government called demokratia, literally translating to “power by the people”, or democracy. But it was not in a form that we might recognize today. It was a direct participatory democracy, where all male citizens could attend assemblies and vote. Some might question the apparent contradiction of a democratic empire, yet to the Athenians the two were intrinsically linked. Athens made the revolutionary decision to make public offices paid positions to allow for men of lower social classes to participate.


But not every citizen could attend every assembly, which meant that the composition of each assembly was unique. This gave the Athenian government flexibility to change their laws as needed and ensured that the assembly could curtail the power of any office or institution that got out of hand. However, the ability of any assembly to overturn the decision of a previous one made Athens appear untrustworthy to some allies.


A main issue with this new form of government was accountability. Unlike a monarchy or oligarchy where a small number of people could be held responsible, the mass participation in Athens made accountability for mistakes difficult. When faced with failure, the assembly usually laid blame at the feet of the one who proposed the measure or the one who enacted it. There was also a general lack of vision for the empire, since every participating citizen was sovereign and could have their own idea of what Athens should be. Statesmen came to realize that if one were able to control the assembly, they could in effect control the empire.


The Problem of Pericles

pericles british bust
Roman copt of a Greek bust of Pericles, 2nd Century CE. Source: British Museum


Pericles was a statesman who was preeminent in Athenian politics for decades. By the time of the Peloponnesian War in 431 BCE he had been strategos, a military general, for 20 straight years. This was more a testament to his political charisma than to his martial prowess, however, as the position was decided by a vote in the assembly. Using his unmatched rhetorical skill to command the assembly, Pericles became the de facto ruler of Athens. Under his leadership, the state became an empire, and he started a monumental public building program that reconstructed the Acropolis. Pericles enacted popular policies that helped the working classes, such as lowering the property requirement to hold public offices and offering generous pay to jurymen serving in Athens’s courts. Such were his achievements that by the time of his death in 429 BCE the naval power of Athens was left without a rudder.


Pericles’ preeminence in Athenian politics presented a problem for Athens, since it set a precedent for other men to follow. Other men, according to Thucydides, did not care for the well-being of the state but only for their own personal ambition, and did not have the same rhetorical skill that allowed Pericles to sway the people. The men who came after him always succumbed to the people’s baser desires. The dysfunction in the assembly caused many problems for Athens during the war with Sparta and often paralyzed military operations with indecision and infighting as men vied for supremacy within the assembly. One such man was a nephew of Pericles named Alcibiades, who led Athens in a doomed attempt to subdue Sicily and opened up another front for the war. This expedition would prove disastrous for Athens and her hold on the empire.


Prodding Sparta

hoplite combat amphora lysippides
Terracotta amphora depicting two hoplite warriors in combat, attributed to Lysippides Painter, 530 BCE. Source: The Metropolitan Museum of Art


From the outset of the Delian League, there was friction between Athens and Sparta. Athens gained influence and power throughout the Greek world, and Sparta grew fearful of that power being turned on her. It was inevitable then that the two powers would come into conflict. Yet there were times when the capricious nature of the Athenian assembly only served to hasten that inevitability.


For years Athens had been indirectly engaged in wars with Spartan allies, though due to a peace treaty with Sparta were unable to take direct action. Instead, Athens opted to use different measures. The Megara Decree, enacted by Athens before the outset of the war, was an economic sanction against Sparta’s ally Megara which barred the city from access to any ports within the empire, cutting off the city from the Aegean and Black Sea. The effects were not only disastrous for Megara, but for Sparta as well since Megara was its trade link between the Aegean and the entire Peloponnese. It also undermined one of Sparta’s most powerful allies, Corinth. At the time of the decree, Corinth had begun building a massive armada and sourced their raw materials from the Aegean through Megara. Many scholars cite this moment as a defining cause of the Peloponnesian War.


Even when the Peace of Nikias was signed in 421 BCE, Athens did not intend to honor it. Instead, they allied with Argos, a traditional enemy of Sparta, and through them incited democratic revolutions. This eventually led to direct confrontation with Sparta, culminating in the Battle of Mantinea. Athens was defeated, the alliance with Argos was broken, and the Peloponnesian War resumed.


Alcibiades and the Sicilian Expedition

alcibiades socrates aspasia ansiaux
Alcibiades and Socrates in the Home of Aspasia, Antoine Ansiaux, 1831. Source: University of Notre Dame


Alcibiades was a nephew of Pericles and a leading statesman in Athens after his uncle’s death. He was also a fierce advocate for war against Sparta. Alcibiades aimed to emulate his uncle’s preeminence over the assemblies and he perfectly exemplified the character of imperial Athens. On the surface he was handsome, well-spoken, and well-connected, but underneath he was duplicitous and self-serving. He cared for the prestige of Athens only so far as it increased his own, and he would sooner see the city fall than have her headed by anyone else.


When representatives from the Sicilian city of Segesta arrived in Athens in 415 BCE to ask for aid in a war against one of their neighbors, Alcibiades jumped at the opportunity despite the fact that they were still embroiled in a war with Sparta. He convinced the assembly that this new campaign would bring them riches and allies, and would reinvigorate their efforts against Sparta, but internally he saw the expedition as a chance to increase his own wealth and power through the conquest of Syracuse.


The expedition to Sicily met with near-immediate disaster. Firstly, the Segestans did not have the money they promised. Secondly, they were having difficulty finding allies among the cities of southern Italy. Lastly, Alcibiades was recalled to Athens to stand trial on charges of impiety. Knowing that his enemies back home would fix the trial against him, Alcibiades fled. But he didn’t go far.


Alcibiades Abroad

alcibiades socrates teacher pupil
Alcibiades Being Instructed by Socrates, C.W. Eckersberg, 19th Century. Source: Bertel Thorvaldsen’s Art and Collections


Defecting to Sparta, Alcibiades dealt with their kings and told them of Athens’s intentions in Sicily, advising them to send aid to Syracuse and to occupy the town of Deceleia, a strategically important trade route near Athens. By his advice, Athens was defeated in Sicily, a force of nearly 60,000 entirely wiped out. Alcibiades’ fortunes would run out in Sparta after he seduced and impregnated the king’s wife, and he then fled to Athens’s traditional enemy and incentive behind the formation of the Delian League, Persia.


From Persia, Alcibiades masterminded a coup against Athens’ democracy as a means of affecting his own recall and returning to the city as a savior. His plan worked and soon after his recall the insurrectionists at Athens were overthrown and a democracy reinstated. He went on to win several other victories for the Athenians, but when his fortune turned, so did his support in the assembly. He was stripped of his command and went into a self-imposed exile, never returning to Athens.


The Fall of Athens

athena parthenos bust broken
Roman copy of a bust of Athena Parthenos, 2nd century CE. Source: The Metropolitan Museum of Art


It only took two years after Alcibiades exiled himself for the Athenian empire to fall. The ever-shifting whims of the assembly were the final nail in Athens’s coffin and by 406 BCE the empire was in dire straits. The Sicilian expedition was a disaster, the Ionian cities along the coast of Asian Minor were in revolt, and Sparta had amassed a powerful navy on par with Athens itself. Both sides needed rowers to man the oars, who were most often slaves, so Athens decided the best way to enlist and ensure the loyalty of the rowers was to offer them freedom and citizenship after their service. This decision was no doubt made by the assembly but, after the battle of Arginusae where Athens defeated the Spartan fleet, the people held a trial against their victorious generals.


The charges brought against the generals were that they did not rescue survivors or bury their dead, the latter being a serious crime in Athens and both warranting punishment. Historian Peter Hunt suggests another underlying factor. The Athenians were irate at the prospect of losing their property — to free another man’s slave was the act of a tyrant — and laid the blame squarely at the generals’ feet.


So, the assembly held a trial and ultimately condemned the generals to death. In one swoop Athens had rid itself of all of its best generals and admirals. After this, it did not take long for Sparta to overwhelm the Athenians and put the city under siege. In 404 BCE Athens formally surrendered.


temple poseidon cape sounion greece
Temple of Poseidon at Cape Sounion, Greece, c. 2018. Source: Wikimedia Commons


The empire of Athens, as of its transition from the Delian League, lasted only 50 years. Some people born at its inception were still alive by its fall and saw their once democratic city become an oligarchy controlled by their enemy. This outcome was due to the Athenian people themselves. The self-serving and capricious nature with which they governed their empire led to their ultimate defeat. They inspired no loyalty in their allies, were actively mistrusted, and internal power struggles led them to make short-sighted and disastrous decisions.

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By Daniel SoulardBA Classical CivilizationsDaniel holds a Bachelor’s degree in Classical Civilizations from Concordia University, Montreal, and is currently applying for his Master’s in the same field. His area of interest are Greek history from the Classical period through the conquests of Alexander the Great, as well as the ancient Greek language. He loves nothing more than to share his passion for history with anyone who will listen, and even with those who won’t.