Almost as soon as it was published in 1532, The Prince was derided as a controversial, heretical work. Sidney Angelo collected a handful of these early reviews that he found during his research:

Throughout the sixteenth and seventeenth centuries we find Machiavelli depicted as the very hand of the devil; as an "imp" of Satan, as "hell-bourne", as a "damnable fiend" of the underworld, as the "great monster-master of hell." John Donne once went so far as to describe a vision of the netherworld in which Machiavelli, attempting to gain a place in Lucifer's innermost sanctum, was out-argued by Ignatius Loyola, founder of the Jesuits. And it was even possible for Samuel Butler to suggest, facetiously, that "Old Nick" himself took his name from "Nick Machiavelli."

The Prince was placed on the Papal Index of Prohibited Books in 1559, but historians disagree as to whether this was for religious or political reasons.

More telling is the scathing reaction to Machiavelli by English minister Richard Harvey in his treatise A Theological Discourse of the Lamb of God and His Enemies (1590). After discussing how much Machiavelli's anti-Christian philosophy sickened him, comparing him to a spider who has gathered his venom from "old philosophers and heathen authors," Harvey warns to his readers:

Be not deceived, God is not mocked, for whatever a man soweth that he shall also reap for he that soweth to the flesh, shall of the flesh reap corruption, but he that soweth to the spirit, shall of the spirit reap life everlasting.

Given that the purpose of The Prince was to raise revolutionary ideas—rejecting the old morality in favor of a new one—it is hardly surprising that early critics might find Machiavelli disturbing and heretical.

However, by the nineteenth century, critics became interested in Machiavelli's purposes for writing The Prince. His theories of moral relativism were no longer shocking. The ideas that Machiavelli had been condemned for were known all over the world. Critics began to praise him for his honesty and insight into the political arena.

For instance, Lord Macaulay Thomas Babington asserted in 1827 that ordinary readers could be expected to view Machiavelli as the most depraved and shameless of human beings, but that, in fact, "[h]is works prove, beyond all contradiction, that his understanding was strong, and his sense of the ridiculous exquisitely keen."

By the end of the 1800s, Machiavelli's ideas had become so commonly accepted that critics seldom felt the need to soften their praise of him. The introduction to the 1891 edition of The Prince contained glowing praise from the eminent sociologist Lord Acton John Emerich Edward Dalberg-Acton.

Dalberg-Acton rejected the moral objections to Machiavelli's work, maintaining that they may be legitimate but that his great contribution to the world of political discourse made them necessary. He praised Machiavelli as "the earliest conscious and articulate exponent of certain living forces in the present world," contending that the events that had occurred since the publication of the book had only served to make his ideas more relevant.

Twentieth-century students of Machiavelli have addressed his personal motives for writing The Prince. Critic Garrett Mattingly ridiculed the idea of the book as a serious guide. In fact, Mattingly made the case that the book's apparent attempt to aid and justify dictators contradicts everything else that Machiavelli wrote.

The book must be a satire of totalitarian rulers, Mattingly concluded, written at a time when its author would have been most hesitant to openly criticize political leaders—when he had just been freed from jail.

Many other recent critics have examined the specific question of what is meant by Virtu. Entire books have been written debating Machiavelli's meaning, while other critics have concluded that he had no set meaning for the word at all.

Interestingly, the word "Machiavellian" is still used as an insult—implying dishonesty and greed—but there is seldom a question of Machiavelli's historical importance.