The Cathedral Basilica of Saint Denis (French: Cathédrale royale de Saint-Denis, or simply Basilique Saint-Denis, previously the Abbaye de Saint-Denis) is a large medieval abbey church in the commune of Saint-Denis, now a northern suburb of Paris. The abbey church was created a cathedral in 1966 and is the seat of the Bishop of Saint-Denis, Pascal Michel Ghislain Delannoy. The building is of unique importance historically and architecturally.
The site originated as a Gallo-Roman cemetery, in late Roman times – the archeological remains still lie beneath the cathedral; the people buried there seem to have had a faith that was a mix of Christian and pre-Christian beliefs and practices. Around 475 St. Genevieve purchased some of the land and built a church. In the 7th century, the earlier church was replaced by a much grander construction, on the orders of Dagobert I; it is claimed that Dagobert also moved the body of Saint Denis, a patron saint of France, to the building.
According to legend, Saint Denis was the first bishop of Paris. Legend says that he was decapitated on the Hill of Montmartre. To account for his tomb being at Saint Denis, several miles away, legend states that Denis carried his head to the site of the current church, thereby indicating where he wanted to be buried.