If you're looking at the broad picture of the evolution of sapiens, then the epochs are hunter-gatherer, farming community, and then the founding of cities and city-states.
In times of peace, when business was bad, Hawkwood and his men would march into a city-state and, after burning down a few farms, would offer to go away if protection money was paid to them.
Known for instilling fear in the hearts of their enemies at the very sight of them, this ancient Greek city state rocketed back into public consciousness with Zack Snyder's infamous film, " 300" .
A generation before these sculptures were made, Athens was one of a number of fiercely competitive city states, who were suddenly forced into a coalition with each other by the Persian invasion of the Greek mainland.
Whenever the Italian city-states were at war with each other, Hawkwood used to hire his soldiers to princes who were willing to pay the high price he demanded.
Over the next couple centuries, different states shifted around their allegiances but by the 14th century, Modena was all aboard team Roman Emperor and Bologna was on Team Pope.
Some problems could be handled by increasing the number of magistrates, or by letting conquered city-states continue to rule themselves under Roman guidance.