Machiavelli describes three ways to hold states that have been accustomed to living freely under their own laws. The first is to devastate them. The second is for the conqueror to occupy them. The third is to allow the state to maintain its own laws, but to charge taxes and establish an oligarchy to keep the state friendly. The third option is advantageous because the newly imposed oligarchy will work hard to secure the authority of the conquering prince within the conquered state because it owes its existence to the prince and cannot survive without his support. Thus, as long as the goal is not to devastate the other state, it is easiest to rule it through the use of its own citizens.
Complete destruction is the most certain way of securing a state that has been free in the past. A prince who does not take this route places himself in a position to be destroyed himself. No matter how long it has been since the state was acquired, rebellions will always revive the legacy of ancient institutions and notions of former liberty, even if the state has benefited from the prince’s rule. This sense of tradition will unify the people against the prince.
On the other hand, cities or provinces that are accustomed to being ruled by a prince are easy to take over once the ruling family has been destroyed. People in such states are accustomed to obedience and do not know how to live in freedom without having someone to rule over them. Therefore, the new prince can win the province and hold onto it more easily.
In republics (or former republics), sentiments of hatred and revenge against the conquering prince will run strong. The memories of ancient liberty never die, so a prince will be better off destroying the republic or personally occupying the conquered state.
[P]eople are by nature changeable. It is easy to persuade them about some particular matter, but it is hard to hold them to that persuasion.See Important Quotations Explained
Princes should strive to imitate the examples set by great rulers of the past, even if that means setting lofty goals. This way, if a prince fails to meet those lofty goals, his actions will nevertheless enhance his reputation as a great or powerful ruler.
One way that rulers acquire states is through their own prowess, meaning their own abilities, rather than the good fortune of noble birth, inheritance, or lucky circumstances. Relying on one’s personal prowess is a very difficult method of acquiring a state. However, a state acquired by a ruler’s natural skill will prove easier to maintain control over. Examples of rulers who triumphed on the strength of their own powers include Moses, Cyrus, Romulus, and Theseus.