The Greeks mostly depended on the sea because that's how they had access to fish and trade. As the population grew they had to form city-states. They called it a polis, and it means a city-state in ancient Greece. Each city-state had its government and seats of laws. They had in an oligarchy are a group of wealthy people who held power over a larger group of citizens. Some city-states were runned by democracies, which means people taking part in running there government. The two most important city-states were Sparta and Athens. Sparta was an oligarchy they were ruled by two kings. They believe in war and self-discipline. Sparta doesn't believe in free speech and new ideas. On the other hand, Athens believed in new ideas and change, instead of being thought violence in school they learned geometry, music, and art, etc.