This is Caterina Sforza, one of the most infamous people of Renaissance Italy. She had many feuds, the most prominent of which was with the Borgia family. This feud resulted in an interesting rumor—that she weaponized the Plague, and tried to assassinate the Pope with it.
No one claims that Caterina Sforza was a nice woman, but she didn’t live during a nice time. The daughter of a family of condottieri (aka a group of violent mercenary thugs), she became the wife of the notoriously cruel Girolamo Riario, the Lord of Forli.
Caterina eventually became known as the Tigress of Forli—a reputation she earned when her husband was killed by rebels. She persuaded the rebels to let her into a fortress being held by people loyal to her husband, claiming she could get the leader to surrender the fortress to them. Once inside, she secured the fortress and screamed obscenities at the rebels. The rebels, who had kept her children as insurance against her doing exactly what she did, brought out her kids and threatened to kill them. Caterina yanked up her dress and screamed, “Kill them. I can make more.”
That was the beginning of her career as a warlord. Her second most famous exploit came towards the end of her career—a career spent murdering, torturing, and feuding with everyone around her. Pope Alexander VI (also known as Rodrigo Borgia) was in office. She didn’t like him. In 1499, she sent him some letters, wrapped in scarlet cloth, and completely enclosed within a wooden cane.
Some claim that Caterina either imbued the cloth or the letters with poison. Perhaps it was a slow-acting poison that could be dissolved through the skin, or maybe it was meant to kill the Pope via poisonous fumes that would erupt when the letters were burned. It is possible that she poisoned the letters somehow. Caterina was a noted alchemist, who kept conducting chemistry experiments after she was removed from power.
Others think that the cloth was infected with the Plague—meaning Caterina was not only attempting the world’s first assassination of a political figure via biological weapons, but probably trying to take out half the people in Alexander’s retinue. If this is true, what would have been most interesting about it is Caterina’s knowledge of the Plague. The fifteenth century wasn’t famous for its medical knowledge. If nothing else, she could have sent Alexander the bedding from a Plague victim.
Of course there are some who say that Caterina never tried to poison the Pope at all. At the time, she didn’t need the kind of action that came with threatening the Pope. And the Borgias weren’t above claiming that someone had taken the first shot at them and then declaring war. In the end, she was deposed and imprisoned by Alexander’s son, only to be let out after Alexander died of natural causes. She spent the rest of her life in semi-retirement, doing her chemistry experiments and coaching her kids and grandkids on how to be just as terrifying as she was.