Britannica Sources used in this answer

Who was St. Januarius and why is he important to Naples?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Saint Januarius (died c. 305 CE) was the bishop of Benevento and is the patron saint of Naples. He is believed to have been martyred during the persecutions of Christians under the Roman emperor Diocletian.12

He remains deeply important to Naples due to a famous relic kept in the Naples Cathedral, which is alleged to be his blood. This solid substance is observed to liquefy 18 times each year. While the phenomenon has been tested frequently, it remains a significant and unexplained event that reinforces his status as the city's protector. Additionally, his historical significance is marked by the Catacombs of St. Januarius on the Capodimonte slope, which serve as a vital site for understanding early Christian history in the region.12