Question

Why is Machiavelli considered the “father of modern political science”?

Answer 1

He wrote one of the first post-medieval books about how a politician (or in this case, as the book is named, The Prince) should go about his job

Answer 2

As many others have pointed out, Machiavelli is unique in being the first (known) political thinker to consider the modern idea of the nation-state and the notion of sovereignty. However, there is another important distinction to make.

While there were other post-Hellenic philosophers who wrote in the field of politics (Augustine may be one), these were all philosophers first who arrived at political theory only as a consequence of their politics. Machiavelli, on the other hand, was the first to approach political science as a independent discipline, concerned with the art of politics rather than the ethic