In ancient times the Greeks lived in city states. Each state had its own laws, government and money but they shared the same language and religion. The two most important city states were Athens and Sparta. We know much about Athens because it produced many writers and artists, whose work has survived to this day.
Ancient Map of Athens and Piraeus: Long walls were built, linking the city of Athens with its port, the Piraeus. Enemies of Athens could not encircle the city and cut off supplies.
Video of the Rise of Athens:
History of Athens: