First I'll explain what a city-state was. It is, simply put a city that is independent from any state or country. The three main ones were Milan, Venice, and Florence. They conquered the other city states. They still exist today though they are now cites within Italy.
The city-states were run by elected leaders and others by ruling families, e.g the Medici family. They often fought with each other. The city-states are now cities in Modern Day Italy.
