Hey there!
Athens was built around 3000BC on the large rock known as the Acropolis. It was founded and based upon Monarchy, Tyranny, and Oligarchy at first, but it eventually was converted to a direct democracy (we use representative democracy today, and so did Ancient Rome, as we're both republics).
After the Greco- Persian wars, a series of wars fought by Athens, Sparta, and other Greek city-states against the mighty Persian empire, Athens created the Delian league- a league made up of many city-states from the Mediterranean region that Athens taxed in exchange for protection from its powerful navy.
As a result, Sparta made its own league, the Peloponnesian league, and the tension between the two started the Peloponnesian War. In the end, Sparta technically won- but this war weakened Greece overall and Philip the Second of Macedonia used this weakness as an area of opportunity. He seized the moment, sent his army, and took over Greece.
Hope this helps!
