The Peloponnesian War was a conflict between 431-404 BC between the Athenians and the Peloponnesian League led by the Spartans. The Athenians valued excellence and moderation in all things, while the Spartans were a militaristic city-state where 80% of the population were Helots. The war consisted of the Archdamian War, the Sicilian War, and the Ionian/Decelean War, and ended in 404 BC with the surrender of Athens to Sparta.