It formed the Delian League in the second half of the 50-year war, which it turned into an empire of its own when the Persian War ended.
Athens.
Athens.
In order to defeat the Persians in the Second Persian War, Athens built a tremendous fleet and formed an alliance with many seafaring city-states in Greece and Ionia, with Athens at its head. Eventually, the Delian League became the basis for Athenian Empire.
After the Persian War, conflict between the two broke out and culminated in the destructive 27-year Peloponnesian War. In the end, the Spartan alliance developed a war fleet using Persian funds to defeat the hitherto superior Athenian fleet, besieged Athens and starved it into surrender in 404 BCE.
It was a war between Athens and its allies and Sparta and its allies - the latter tried to control the expansionary efforts of the Athenian empire. It lasted from 431 BCE to 404 BCE, when Persian financial intervention swung the war in favour of the Spartan alliance, resulting in the capture of Athens.
during the greeco-persian war...
Athens and Sparta were friendly before the Persian War. They naturally joined the alliance which repelled the Persian invasion. A Spartan force helped Athens retain its government against a revolt pre-war. Athens post-war helped Sparta put down a serf rebellion, but then started to side with the serfs, so the Spartans sent them home. That was the split.
No city won. The Sparta alliance with Persian backing defeated the Athens alliance or empire.
Athens converted the Delian League which it had led in the later phase of the war with the Persian Empire into an empire of its own, and after peace with the Persians it used this power to interfere in the rest of the Greek world, resulting in the devastating 27-year Peloponnesian War.
Athens.
The Persian Empire and an alliance of Greek city-states led first by Sparta and then Athens.
Contrast the results of the Persian and Peloponnesian war with regards to Athens Greece