Answer:
The War fought between the two leading city-states in ancient Greece, Athens and Sparta. Sparta won the Peloponnesian War in 404 BC.The wealth, prestige, policies, and power of Athens caused resentment among other city-states.
One impact it had on Greece was a plague that killed many Athenians helped Sparta defeat Athens. The Peloponnesian War weakened all of the Greek city-states for 50 years.