9. She even had a love affair with her own brother-in-law
Most scandalous of all, Lucrezia had a long sexual relationship with Francesco II Gonzaga, Marquess of Mantua (1466-1519). What made this particular infidelity unacceptable was the fact that Francesco was her brother-in-law. He was married to Isabella d’Este, Alfonso d’Este’s sister. Isabella and Lucrezia did not get along at all well, though their ill feeling predated the affair. Francesco also had syphilis, though Lucrezia doesn’t seem to have caught it. The two bonded over their love of culture, which Lucrezia dated from her unusual schooling as a girl.