Between the 3rd and the 5th centuries AD, a vast necropolis was established on the site. With more than 400 graves, it has now been partially excavated. The deceased were placed in coffins of which archaeologists have sometimes found traces of wood and some nails. Brought to light in 2007, seven stone sarcophagi, aligned on a north-south axis, marked the limit of the necropolis. An eighth sarcophagus is at present being excavated.
During the Merovingian epoch (6th-8th centuries), funeral practices evolved and the necropolis moved towards the south-west. Early in the 7th century, one of the most ancient textual sources, the Testament of Ermentrude, relates the presence of a Church in Bondy, around which the cemetery was created. Previous excavations revealed the presence of plaster sarcophagi, sometimes decorated. The deceased were buried in them dressed, and adorned with belt plates and pins to fasten the clothes.
In 2007, the excavation at the foot of the church revealed graves of plague victims. The deceased, sometimes in groups of five, were placed in multiple graves. This discovery of victims of the terrible 1348 plague is exceptional in the Île-de-France region. Genetic and carbon 14 dating have confirmed this discovery.