The Peloponnesian War: Athens vs Sparta The Peloponnesian War (431–404 BCE) was a pivotal conflict in ancient Greece, fought between the city-states of Athens and Sparta, along with their respective allies. The war arose from long-standing rivalries, as Athens, known for its naval power and democratic governance, and Sparta, renowned for its military discipline and land forces, represented contrasting ideologies and lifestyles. Initially, the war began with the disputes between Athenian imperial