The Peloponnesian wars were based around Athens and Sparta, it started in 459 BC and lasted 15 years. It was very hard to have decisive battles because both sides wanted it on their turf mainly Athens at sea and Sparta on land. The Athenians had a very good navy so they went to Spartas coasts and fought many of the cities. Athens ended its treaty with Megara because Megara and Corinth were allied with Sparta. Athens fought against many of Sparta’s allies and ended up controlling Megara and Aegina. Sparta wanted to end this so they went and struck Athens homeland in Attica. Then they forced Athens to return the lands they had conquered for Attica. They agreed and signed what was called the Thirty years’ peace and they said that they could each have their own ally system.
Athens was the one guilty of breaking the peace, and they did it in three ways.
They imposed trade sanctions on Megara and fought in the battle against Corcyra in which Athens had no stake. They also ordered the walls of Corinth to be torn down.
The Spartan assembly agreed that Athens had broken the peace treaty and started a new round of wars which lasted 17 years. This war was called the Archidamian War. It started with Sparta invading the lands around Athens. But the Spartan army could only stay for forty days because of the harvest. Athens was being run by a navy general named Pericles, and they did well for many years including winning the battle of Naupactus against Sparta.
These wars weakened Athens so Sparta found more allies including Persia, Syracuse, and the Ionians. But after a while, the Ionians rebelled against Sparta from 410 BC to 406 BC. In 406 BC Sparta, led by Lysander, won the naval battle of Notium. Athens surrendered and were then ruled by the Thirty Tyrants that were put in place by Sparta.