Rodrigo de Borja became Pope Alexander VI in 1492. Father of Caesar and Lucretius, he inspired Machiavelli when writing The Prince. The Borgia family, like a three-headed hydra, intrigued against the powerful Renaissance families: the Sforza, the Visconti, the Orsini... In this biography, Jean-Yves Boriaud unravels the thread of this family history, which intertwines with the creation of a papal state, among the resurgent princes of troubled northern Italy. The Black Legend, which will originate with the death of Alexander VI, will allow later criticism of the papacy and will encourage it's in-depth revision. This legend will be taken up by the Protestants in the 17th century then in the 19th century by the Romantics, including Victor Hugo and his famous work Lucrèce Borgia. Jean-Yves Boriaud uncovers the historical truth of these intrigues, plots and mystifications that have spanned the centuries and tells us the true story of this powerful family.