The city-state was the outstanding political achievement of the Greeks. Topographical features of the country and the tribal characteristics of the people were important factors in the development of the City-States. The Polis originated as a fortified site but later was interpreted as a Sovereign State. It included the fort, the city, and the surrounding country side. Around 800 B.C.E, a group of Greek villages began joining into larger units to form City-States.

At the highest point in a city-state, an Acropolis or Citadel was built for defence and the city spread around the Acropolis. Sparta, Athens, Macedonia, Corinth, and Thebes were important City-States. Though the Greek City-States were independent, jealous and quarrelsome, all the Greeks strongly believed that they were all Hellenes. Another bond that united them was the common language and literature. One more factor that united them was the worship of Gods like Zeus, Apollo, and Athena.