A polis was a city-state, which means it was a small region that had its own government and laws. In ancient Greece, there were many different types of cities, each with their own set of rules and customs.
The first polis was founded in the early 8th century BCE on the island of Crete by Minos, the king of Crete at the time. It is believed that he built it to honor Zeus, his patron god, who had helped him defeat his enemies.
The largest and most powerful polis was Athens, which had over 100,000 people living in it at its peak in 350 BCE. Other major cities included Sparta, Corinth and Argos.
The citizens of a polis were called citizens or politai (singular: polites). Each citizen had certain rights and obligations, including military service. All male citizens over 18 years of age were required to serve in the army for 2 months each year. The assembly (ekklesia) met at least once every month to discuss matters of state importance and to vote on issues brought before it by magistrates or other officials. These votes were not always unanimous because people could vote either yes or no but not both in some cases; these votes were recorded on stone tablets kept in a special building called the odeum (or bouleuterion).
In ancient Greece, the polis was often at war with other city-states. Athens and Sparta were two famous examples of this type of conflict.