Delian League vs Persian Empire: The Greeks on the Offensive

After the Greeks thwarted the second Persian invasion of Greece, Athens and its allies decided to go on the offensive and continue the fight.

Sep 14, 2023By Greg Beyer, BA History & Linguistics, Journalism Diploma

wars delian league


The first few decades of the Delian League represented a powerful time for the Athenians. Fresh from defeating two invasions from the Persian Achaemenid Empire, the Greeks, now realizing their martial superiority, sought revenge against the Persians.


Of course, not all the Greek city-states were interested, so under the guidance of Athens, the Delian League was created. At its inception, over 150 city-states joined the League, mainly from the Aegean islands and surrounding areas such as the Ionian coast. With this power, Athens could strike back at the Persians who had sought to subjugate Greece. The wars of the Delian League were a series of campaigns in which the Greek city-states went on the offensive.


The Beginning of the Wars of the Delian League

A Greek vase depicting a hoplite, via Encyclopaedia Britannica


The capture of the Persian garrisons at Sestos and Byzantium in 479 BCE and 478 BCE, respectively, marked an end to the second Persian invasion of Greece. At this point, a decision was made on whether to continue the war or put an end to the hostilities. Sparta, which had played a critical part in defending Greece, opted to return home, while the Athenians decided to continue the war and mount offensive campaigns against Persian holdings. Part of this decision was motivated by the fact that the Persians were still in control of many of the Hellenic cities on the Ionian coast.


Terrace of lions, Delos, Greece, via Wikimedia Commons


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Sparta and her allies represented a sizable chunk of the Greek fighting force, and so Athens initiated a conference on the island of Delos which was considered a sacred site by Greeks from all over the Hellenic world, including the Ionians. From this conference, the Delian League was formed. It consisted of over 150 city-states bound by an oath into a military alliance with Athens as its leader.


The alliance was formed for three main reasons, namely, protection against future invasions from Persia, revenge against Persia, and to fairly distribute the spoils of war. In the words of the ancient Greek historian Thucydides, the reason for the formation of the League was to, “avenge the wrongs they suffered by ravaging the territory of the king”.


From the outset, the Delian League’s policies were aggressive, not only in seeking war with Persia but in expanding the league and policing it. City-states which tried to secede from the League were dealt with brutally and forced back into line with harsh penalties.


The Campaigns Commence

Map of the battles fought by the Delian League against the Persians and against rebel elements within the League, dates are estimates, via Author / Google Earth


The account of the events, according to Thucydides is lacking dates, and historians are unsure of the exact years of the events. Nevertheless, the first action against the Persians was fought at Eion in what was then Thrace in 476/475 BCE. Led by the prominent statesman and general Cimon, the Athenians first defeated the Persians in the field, upon which the latter fled into the city of Eion, which the Athenians then besieged. Starved into submission, the Athenians eventually captured the city after the Persian commander, according to Herodotus, committed suicide. The remaining population was enslaved.


On the return journey, the island of Skyros was captured. Although it wasn’t a Persian asset, the island was a base of operations for piracy throughout the Aegean. After taking the island, many Athenian citizens were moved there, and the island became a colony of Athens.


A decade later, the Delian League took action at Chersonesos (now called Gallipoli), where the Persians had, with the possible help of the Thracians, set up a military outpost. With only 4 ships, Cimon sailed to the peninsula and surprised the Persians, capturing their 13 ships, and proceeding to drive them off the peninsula.


The Battle of Eurymedon

The Eurymedon Vase, depicts (possibly) a Greek man holding his genitals and a Persian with the inscription “I am Eurymedon, I stand bent forward”, this possibly relates to the Battle of the Eurymedon, c. 465 BCE – 460 BCE, via Museum für Kunst und Gewerbe Hamburg


After the defeat of the second Persian invasion of Greece, and the formation of the Delian League, the Athenians were able to operate with impunity throughout the Aegean. For several years, Persia was gripped by internal strife, which hampered the reformation of its military capability. King Xerxes died, and a power struggle ensued, which led to his third son Artaxerxes taking the throne.


It is unclear whether the ascendancy of Artaxerxes took place before or after the Battle of the Eurymedon around 465 BCE / 466 BCE, but whatever the case, the Persians began a significant buildup of ships and troops at Aspendos near the mouth of the Eurymedon River. It is suggested that the Persians intended to sail up the coast of Ionia and subjugate the Greek city-states that had escaped the yoke of the Persian Empire.


Upon hearing of the Persian activities, Cimon took a large fleet of 200 triremes to the southern coast of Asia Minor. With a bit of persuasion, Phaselis joined the Delian League. This city was positioned just to the west of the mouth of the Eurymedon, and the defection of Phaselis deprived the Persians of their first stepping stone to reconquering their lost territories.


Cimon then moved to attack the Persian fleet. The number of Persian ships is estimated to be from 200 to 350 to the Greeks’ 200. When the Persians saw the Greeks coming, they fled with their fleet upriver. The Greeks gave chase and the Persians eventually turned round and gave battle. Grounding their ships, the crews of the ships sought sanctuary with the army, which was then beset by Greek marines.


Not much is known about the battle, but the Greek hoplites, as in the Battle of Mycale, triumphed over their poorly armored foes.


The Invasion of Egypt

A statue of the Greek historian Thucydides, Wikimedia Commons


A few years after the Greek victory at the Eurymedon, Athens seized the opportunity to support the Egyptian revolt against the Persian Empire. Admiral Charitimides, commanding 200 triremes campaigning near Cyprus, diverted the fleet and sailed towards the Nile Delta. They sailed up the Nile to link up with the forces of the rebels who were under the command of the Libyan King Inaros. On their way, they crushed a fleet of 50 Phoenician ships under the command of the Persians.


With the Persian relief force having arrived, the Battle of Papremus (also Pampremus) followed around 460 BCE. Virtually nothing is known about the battle save the fact that the Greeks and the Egyptians overcame the Persian numbers and achieved victory. The Persians fled to the citadel (known as the White Castle) in Memphis, where they took refuge. The Greeks and Egyptians then besieged the city, but after several years they still had not been able to force the garrison to surrender. The Persians were eventually able to send another relief force which broke the siege and forced the Greeks to abandon their positions.


A royal seal depicting Artaxerxes killing the rebel king of Egypt, Inaros, via Internet Archive Book Images


The Greeks then retreated to Prosopitis, an island in the Nile Delta where their ships were moored. The Persians followed them and drained the surrounding water by digging canals, after which they captured the island. The remaining Greeks fled west to Cyrene.


Unaware that their land army had already been defeated, a Greek naval relief force was put in at Mendesium, where they were taken by surprise by Phoenician land and sea forces. The Athenian fleet was quickly destroyed.


The expedition to Egypt had been a disaster for the Delian League, which lost around 50 000 men and 250 ships. To make matters worse, the Delian League was at this time at war with Sparta and her allies, and the defeat wiped out much-needed resources.


Cimon Sails to Cyprus

Ruins of the gymnasium at Salamis, Cyprus, via Wikimedia Commons


After Athens and Sparta signed a five-year truce in 451 BCE, the Athenians were freed to pursue military adventures elsewhere. With a fleet of 200 ships (provided by Athens as well as the rest of the Delian League), Cimon sailed to Cyprus. Forty ships were diverted to support rebel elements that still existed in Egypt. With the remaining 140 ships, the Athenians besieged the city-kingdom of Kitios.


The siege, however, did not go well for the Greeks. Although the cause of death is unknown, Cimon perished, and the Athenians retreated towards Salamis-in-Cyprus, and abandoned their campaign. After defeating a Persian force of Cilicians, Cyprians, and Phoenicians, the Greeks made their escape and were rejoined by the elements of the fleet sent to support the Egyptians.


The End of the Wars of the Delian League with Persia

The Parthenon by Frederic Edwin Church, 1871, via the Met


Modern historians are split on how the wars came to an end. There is some confusion over whether the Treaty of Callias pertained to this point in history, with some historians denying that a treaty was even signed. Either way, the Delian League ceased its conflict with the Persians and focused solely on its war with the Peloponnesian League which would flare up again. 


Ultimately, the Delian League failed to achieve what it wanted against the Persians. Too many defeats and the war with the Spartans meant that the Athenians had to abandon further campaigns against their long-time foes in the east.


The conflict would not be revisited. At the end of the Peloponnesian War, Athens was defeated by the Peloponnesian League. The days of Athenian power were over, and Greece entered a new age.

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By Greg BeyerBA History & Linguistics, Journalism DiplomaGreg specializes in African History. He holds a BA in History & Linguistics and a Journalism Diploma from the University of Cape Town. A former English teacher, he now excels in academic writing and pursues his passion for art through drawing and painting in his free time.