Nicasius of Rheims was a 4th or 5th-century bishop of Reims who lived during the era of Ancient Rome. He is primarily remembered for establishing the original Reims Cathedral and for his courageous stance during the barbarian invasions. According to tradition, he met a violent end at the hands of invaders, either the Vandals or the Huns, while attempting to protect his people. Because he reportedly survived a bout of smallpox, he is venerated as a patron saint for those suffering from the disease.