Gilles de Rais was a French lord and knight who served as a leader in the French army. Rais' achievements as a military man are often overshadowed by the fact that he was convicted of killing several children. A confessed serial killer, Gilles de Rais was sentenced to death and hanged on 26 October 1440.
While he was diagnosed with mental illness as a child, French physician Marcel Petiot or Doctor Satan, allegedly killed almost 60 people later. He targeted Jews fleeing Nazi-occupied France, injected them with poison, stole their belongings, and hid their bodies in his basement. He was guillotined for his crimes.