Being beheaded can really mess up your day. But according to Christian tradition, after Saint Denis was decapitated, he simply picked up his head and kept walking and preaching. So it’s perhaps no surprise that Denis (pronounced “duh-KNEE” in French) is the patron saint of headaches.
Paris, however, was still largely a pagan city. And the Parisians didn’t take kindly to Denis converting so many to Christianity. They took Denis and two of his companions to the highest hill in Paris — Montmarte — and decapitated them.