Founding of the Delian League: What Happened
In 478 BC, soon after the defeat of the Persian invasion, Athens and many Greek cities of the Aegean islands and Asia Minor formed an alliance to continue the war against Persia, free the Greeks still under Persian rule and protect against future attacks. It is known today as the Delian League, because its treasury and meetings were based on the sacred island of Delos, birthplace of Apollo. Sparta had withdrawn from leading the war, and the allies turned to Athens, which had the strongest navy. The Athenian statesman Aristides, known as the Just, set the contributions each member would pay, either in ships or in silver. Over time, most members chose to pay money rather than supply ships, which Athens used to build and man its own fleet. This made Athens ever more powerful and the allies ever more dependent. Members who tried to leave, such as Naxos and Thasos, were forced back in. Within a few decades, the Delian League had turned into what historians call the Athenian Empire.
Frequently Asked Questions
What was the Delian League?
The Delian League was an alliance of Greek cities led by Athens, founded in 478 BC to continue the war against Persia and protect the Aegean. Its treasury was originally kept on Delos.
Why was it called the Delian League?
It was named after the sacred island of Delos, birthplace of Apollo, where the alliance's treasury was kept and its members met, until the treasury moved to Athens in 454 BC.
Who was in the Delian League?
Members included many cities of the Aegean islands, the coast of Asia Minor, Thrace and the Hellespont. At its height, more than 150 cities paid contributions.
How did the Delian League become the Athenian Empire?
Most members paid money instead of providing ships, which Athens used to build its own fleet. Athens gained growing control and forced members that tried to leave, such as Naxos and Thasos, to stay.
Can you visit Delos?
Yes. Delos is a UNESCO World Heritage Site near Mykonos, with extensive ruins of temples, houses and the Terrace of the Lions. It is usually visited as a day trip by boat from Mykonos.


