Saint Denis of Paris was a 3rd-century Christian martyr and saint who suffered under the persecution of the emperor Decius shortly after AD 250. According to his hagiographies, he was bishop of Paris (then Lutetia) in the third century and was martyred for his faith by decapitation. Denis is the most famous cephalophore of Christian Faith, with a tradition claiming that the decapitated bishop picked up his head and walked several miles while preaching a sermon on repentance. He is venerated in the Catholic Church as the patron saint of France and Paris and is accounted one of the Fourteen Holy Helpers. Specifically, Denis is invoked against diabolical possession and headaches. A chapel was raised at the site of his burial by a local Christian woman; it was later expanded into an abbey and basilica, around which grew up the French city of Saint-Denis, now a suburb of Paris. The feast of Saint Denis had been celebrated on October 9th since at least the year 800.