Cesare Borgia, 1475-1507 No one ever took the opportunities that a powerful father offered more eagerly than Cesare Borgia. His father was pope Alexander 6th, and his nepotism would be beyond belief if it were not for the examples of the other renaissance pontiffs. Made a cardinal at 15, he was so patently unsuited for the role he was allowed to resign following the death of his brother. He was the first person ever to reject the red hat. He may or may not have been involved in his brother's murder. I say " Not Proven". He still influences history, as Machiavelli used him as the model of the ideal ruler, The Prince. This guy was busy every day of his short life. https://en.wikipedia.org/wiki/Cesare_Borgia He was a fantastic athlete, a great warrior, and a very able ruler. He was very cruel on occasion, and tried to kill his sister's husband in front of the pope. Later he had him strangled, and made no bones about it...