He owed no benefits to Cesare; he was the ambassador of a power that was ever inimical to the Borgias; so that it is not to be dreamt that his judgement suffered from any bias in Cesare's favour.

Yet he accounted Cesare Borgia--as we shall see--the incarnation of an ideal conqueror and ruler; he took Cesare Borgia as the model for his famous work The Prince, written as a grammar of statecraft for the instruction in the art of government of that weakling Giuliano de'Medici.
Macchiavelli pronounces upon Cesare Borgia the following verdict: "If all the actions of the duke are taken into consideration, it will be seen how great were the foundations he had laid to future power.

Upon these I do not think it superfluous to discourse, because I should not know what better precept to lay before a new prince than the example of his actions; and if success did not wait upon what dispositions he had made, that was through no fault of his own, but the result of an extraordinary and extreme malignity of fortune." In its proper place shall be considered what else Macchiavelli had to say of Cesare Borgia and what to report of events that he witnessed connected with Cesare Borgia's career.
Meanwhile, the above summary of Macchiavelli's judgement is put forward as a justification for the writing of this book, which has for scope to present to you the Cesare Borgia who served as the model for The Prince.
Before doing so, however, there is the rise of the House of Borgia to be traced, and in the first two of the four books into which this history will be divided it is Alexander VI, rather than his son, who will hold the centre of the stage.
If the author has a mercy to crave of his critics, it is that they will not impute it to him that he has set out with the express aim of "whitewashing"-- as the term goes--the family of Borgia.

To whitewash is to overlay, to mask the original fabric under a superadded surface.

Too much superadding has there been here already.