Final answer:
Cesare Borgia, the son of Pope Alexander VI, was the conniving Borgia son referred to in the question. His ruthless tactics in reclaiming the Papal States for the Vatican during his father's pontificate made him the model for Niccolò Machiavelli's book 'The Prince'.
Step-by-step explanation:
The conniving Borgia son referred to in the question, whose policies were so ruthless that Machiavelli cited him as an example of a new prince, is Cesare Borgia. Cesare Borgia, a cardinal-turned-legitimized-son of Pope Alexander VI, was known for his strategic mind and ruthless tactics in reclaiming the Papal States for the Vatican during his father's pontificate. In fact, he served as a model for Niccolò Machiavelli's book The Prince, which outlined strategies for political leadership.
Cesare's approach, much like those of many successful leaders in the ruthless world of politics and warfare of the time, relied heavily on the use of military force, strategic alliances, and a general disregard for traditional moral or ethical considerations. Thus, despite the negative reputation the Borgias have earned over the centuries, Cesare's effectiveness in consolidating his father's power in Italy could not be denied, and thus he served as a fitting example of Machiavelli's 'new prince'.
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