Botticelli painted her, Machiavelli slandered her. She led troops into battle, married a Medici, and was imprisoned by the Borgias. Between her birth in 1463 as the illegitimate daughter of the Duke of Milan, to her death in 1509 as a member of the powerful Medici family, Caterina Sforza's life crossed the firmament of Italy's High Renaissance like a shooting star.