On the return of the Medici, Machiavelli, who for a few weeks had vainly hoped to retain his office under the new masters of Florence, was dismissed by decree dated 7th November 1512. Shortly after this he was accused of complicity in an abortive conspiracy against the Medici, imprisoned, and put to the question by torture. The new Medicean pope, Leo X, procured his release, and he retired to his small property at San Casciano, near Florence, where he devoted himself to literature. In a letter to Francesco Vettori, dated 13th December 1513, he has left a very interesting description of his life at this period, which elucidates his methods and his motives in writing "The Prince." After describing his daily occupations with his family and neighbours, he writes: "The evening being come, I return home and go to my study; at the entrance I pull off my peasant-clothes, covered with dust and dirt, and put on my noble court dress, and thus becomingly re-clothed I pass into the ancient courts of the men of old, where, being lovingly received by them, I am fed with that food which is mine alone; where I do not hesitate to speak with them, and to ask for the reason of their actions, and they in their benignity answer me; and for four hours I feel no weariness, I forget every trouble, poverty does not dismay, death does not terrify me; I am possessed entirely by those great men. And because Dante says:

     Knowledge doth come of learning well retained,
     Unfruitful else,

I have noted down what I have gained from their conversation, and have composed a small work on 'Principalities,' where I pour myself out as fully as I can in meditation on the subject, discussing what a principality is, what kinds there are, how they can be acquired, how they can be kept, why they are lost: and if any of my fancies ever pleased you, this ought not to displease you: and to a prince, especially to a new one, it should be welcome: therefore I dedicate it to his Magnificence Giuliano. Filippo Casavecchio has seen it; he will be able to tell you what is in it, and of the discourses I have had with him; nevertheless, I am still enriching and polishing it."

The "little book" suffered many vicissitudes before attaining the form in which it has reached us. Various mental influences were at work during its composition; its title and patron were changed; and for some unknown reason it was finally dedicated to Lorenzo de' Medici. Although Machiavelli discussed with Casavecchio whether it should be sent or presented in person to the patron, there is no evidence that Lorenzo ever received or even read it: he certainly never gave Machiavelli any employment. Although it was plagiarized during Machiavelli's lifetime, "The Prince" was never published by him, and its text is still disputable.

Machiavelli concludes his letter to Vettori thus: "And as to this little thing [his book], when it has been read it will be seen that during the fifteen years I have given to the study of statecraft I have neither slept nor idled; and men ought ever to desire to be served by one who has reaped experience at the expense of others. And of my loyalty none could doubt, because having always kept faith I could not now learn how to break it; for he who has been faithful and honest, as I have, cannot change his nature; and my poverty is a witness to my honesty."

Before Machiavelli had got "The Prince" off his hands he commenced his "Discourse on the First Decade of Titus Livius," which should be read concurrently with "The Prince." These and several minor works occupied him until the year 1518, when he accepted a small commission to look after the affairs of some Florentine merchants at Genoa. In 1519 the Medicean rulers of Florence granted a few political concessions to her citizens, and Machiavelli with others was consulted upon a new constitution under which the Great Council was to be restored; but on one pretext or another it was not promulgated.

In 1520 the Florentine merchants again had recourse to Machiavelli to settle their difficulties with Lucca, but this year was chiefly remarkable for his re-entry into Florentine literary society, where he was much sought after, and also for the production of his "Art of War." It was in the same year that he received a commission at the instance of Cardinal de' Medici to write the "History of Florence," a task which occupied him until 1525. His return to popular favour may have determined the Medici to give him this employment, for an old writer observes that "an able statesman out of work, like a huge whale, will endeavour to overturn the ship unless he has an empty cask to play with."

When the "History of Florence" was finished, Machiavelli took it to Rome for presentation to his patron, Giuliano de' Medici, who had in the meanwhile become pope under the title of Clement VII. It is somewhat remarkable that, as, in 1513, Machiavelli had written "The Prince" for the instruction of the Medici after they had just regained power in Florence, so, in 1525, he dedicated the "History of Florence" to the head of the family when its ruin was now at hand. In that year the battle of Pavia destroyed the French rule in Italy, and left Francis I a prisoner in the hands of his great rival, Charles V. This was followed by the sack of Rome, upon the news of which the popular party at Florence threw off the yoke of the Medici, who were once more banished.

Machiavelli was absent from Florence at this time, but hastened his return, hoping to secure his former office of secretary to the "Ten of Liberty and Peace." Unhappily he was taken ill soon after he reached Florence, where he died on 22nd June 1527.