If you were an ancient Roman, which I accept you’re probably not, today would be one of the three days of the year when the gates to the underworld would be ceremonially opened and the spirits of the dead would be able to commune with the living.
The ceremony seems like a sort of cross between Harvest Festival and Halloween. In the centre of Rome there was a pit known the mundus (world) of Ceres, which was usually sealed with a stone. The pit was said to contain the entrance to the underworld and on August 24th, October 5th and November 8th, the stone would be removed and an announcement made: “mundus patet” (the mundus is open). Then offerings of the first fruits of the harvest would be made to the gods of agriculture and of the underworld.
Ceres is a goddess of agriculture who also has links to the world of the dead. According to her mythology, her daughter Proserpina was abducted by Pluto, the god of the Underworld. Ceres looked everywhere on the earth for her daughter but only found her belt floating in a lake. She was so angry that she stopped the growth of all fruit and vegetables. Everywhere she went, the land became desert. Jupiter was naturally concerned and sent his messenger Mercury to order Pluto to free Proserpina so she could return to her mother. Pluto had to obey, but before she left he made her eat six pomegranate seeds. Anyone who ate the food of the dead could not return in any permanent way to the world of the living. So every year Proserpina can spend six months with her mother but then has to return to the underworld for the following six months. This story represents the changing seasons. In Spring, Ceres welcomes her daughter and everything begins to grow. But when she has to leave again everything dies and we have Winter.
Legend tells us that the mundus was dug by Romulus when he founded the city. He threw into it the first fruits of his new city. Then he gathered all his followers, who came from far and wide and had them cast a handful of soil from their homeland in with the fruits. Then, using the pit to mark the centre he ploughed a circular trench around it that marked where the city walls would be built. The plough share was lifted from the ground at the places where the gates would be. The ceremonially ploughed trench made the walls holy. But they didn’t want the gates to be holy because it would have meant blessing everything that came into the city, and that would have taken ages.
During the days that the mundus was opened to allow offerings to be made, there were no marriages and the temples remained closed. It was believed to be a very dangerous time. It was a particularly bad time to embark on a battle. The souls of the living could be easily called to the underworld.