July 22, 1630 - Madame de Brinvilliers

Marie-Madeleine d'Aubray, Marquise de Brinvilliers (French: [bʁɛ̃vilje]; 22 July 1630 – 16 July 1676) was a French aristocrat who was convicted of murdering her father and two of her brothers in order to inherit their estates. After her death, there was speculation that she tested her poisons on upwards of 30 sick people in hospitals and street dogs, but these rumours were never confirmed.

Content sourced from en.wikipedia.org/wiki/Madame de Brinvilliers under CC BY-SA 4.0.