In Chapter 5 Niccolò Machiavelli is interested in how to govern states which are used to liberty. In this case, the prince must either suppress the old laws, live in the state, or oppose a tax and appoint a friend as leader. In his view, it is easiest to allow the city "to live in liberty according to the customs of its citizens, except in republics, where it is better to control the city by ruining it.
The chapter gives reference of this tactic of trying to conquer republic states one that are accustomed to their own system of rulership. He mentions Sparta and its attempt to absorb its neighboring states Thebes and Athens which did not go well for the Spartans since the states mentioned were already accustomed to their own systems and would rally to quickly appose their oppressors (this being the Spartans)
But the hold over the states did not last and the Powerful Spartan empire fell after exhausting there army down after many continuous conflicts with their neighboring states later on Sparta would fall to Thebes. History has a way of repeating itself because later on Rome would also secure Athens and Thebes after conquering Macedonia in the time of Alexander the Great the person in which the chapter is dedicated its writings to.