Athena did.
The Peloponnesian War ended in 404 BCE with the defeat of Athens which was stripped of its empire and became a second rate state. Leader of the victorious Peloponnesian League, Sparta, assumed leadership until it was defeated by Thebes in 371 BCE, which took over leadership until Macedonia took control in 338 BCE.
The Peloponnesian War-
Athens lost the Peloponnesian War because it was overconfident. It took severe losses over the unexpected 27 years of the war, and eventually Persia bankrolled at competitive fleet for the opposing Peloponnesian League led by Sparta. Athens lost its fleet, and so was starved into submission.
A series of disputes between Athens and the Peloponnesian League led by Sparta came to a head when Athens took action against one of the League members Megara. Sparta tried to get Athens to relent, Athens refused, and war broke out.
Many Greeks outside of Athens resented Athenian domination. Before long, the Greek world split into rival camps. To counter the Delian league, Sparta and other enemies of Athens formed the Peloponnesian League, while Athens supported the among its allies That is why the Peloponnesian War took place.
At the risk of sounding like a smart aleck, it was fought in Peloponnese. The Peloponnesia War was principally between Athens and Sparta. Sparta is located in Peloponnesian Greece, which is the large southern peninsula of Greece. Additionally, battles took place at Athens, along Grecian coasts, and among territory held by both the Athenian and Spartan empires.
When Athens used its navy to good effect during the 27-year Peloponnesian War, Sparta realised that it had to get the Peloponnesian league an equally strong nave to succeed. They took money from Persia to build a fleet which finally destroyed the Athenian navy and led to Athens' surrender.
The first limited democracy was established by Cleisthenes in 507 BCE. It disappeared when the aristocrats took over to repel the Persian invasion, and was restored by Ephialtes in 460 BCE. He was assassinated for doing this, and his protégé Pericles took over and extended it to a radical democracy which shifted all control to the popular assembly. This lasted until Athens' defeat in the Peloponnesian War in 404 BCE, after which Athens returned to a directed democracy.
Because it one side was based in the Peloponnesian Peninsula, home of the Dorian Greeks led by Sparta.- the other side was the empire established by Athens. The fighting was initially around the Peloponnese Peninsula, but it spread throughout the Greek world east to Asia Minor and west to Sicily as the war continued over its 27-year course.
Athens, then Sparta lost preeminence, Persia asserted authority with the Kings's Peace, Macedonia came to preeminence then took over the Persian Empire, and Greece was taken over by Rome. In other words, the Greek world was devastated by the Peloponnesian War, and other cohesive states were able to dominate the weakened and divided Greek city-states.
It was the other way around. Athens adopted a radical democratic system, and this was a contributing cause of it getting involved in the Peloponnesian War and losing it. After losing the war and its empire, the citizens took less interest in democracy and reverted to less democratic forms of government.
King Philip II of Macedonia