A post from 2012:
Since the Showtime Borgia series began I have been pointing out what is fact and what is fiction. (I know the difference because I worked hard to keep the history accurate in my historical mystery, A Borgia Daughter Dies.) The series has strayed further and further from the historical record, and become stranger and stranger in the process. The truth about the Borgias is so dramatic and bizarre that it's hard to understand why Showtime felt it necessary to create so much fiction.
If you want to learn the true history of the Borgias in a fun way, read my e-mystery, A Borgia Daughter Dies, which is getting great reviews on Amazon. If you have any difficulty telling fact from fiction you can look at the Cast of Characters and Afterword at the back and sort things out right away. Get it here: https://www.amazon.com/Borgia-Daughter-Dies-history-Machiavelli-ebook/dp/B007WONQV2/ref=sr_1_1?ie=UTF8&qid=1501519534&sr=8-1&keywords=A+Borgia+Daughter+Dies
Season 3 so far is completely fictional, though Lucrezia Borgia did marry Alfonso of Naples. While there were undoubtedly assassination attempts on Pope Alexander–Caterina Sforza sent him a gift wrapped in blankets from a plague victim, for example- none came close to success until–well, I'll save that for later. Suffice it to say, nothing happened remotely resembling the poisoning and attempted stabbing we have seen in the past few episodes.(Did any one notice that Showtime has now killed Cardinal Orsini twice? Ironically, in the historical chronology he hasn't died yet.)
The characters no longer bear much resemblance to the historical figures, either. Instead, Cesare Borgia, who was a sociopath, probable rapist and the worst of the family is being portrayed as a relative innocent, while the one innocent in the family–his sister Lucrezia, who was by all accounts an admirable and capable woman–has been turned into an incestuous whore. For shame, Showtime!