This first of the three Christmas masses was originally celebrated by the Pope towards midnight in the chapel of the Santa Maria Maggiore Basilica in Rome before a small congregation. Pope Sixte III had constructed this small chapel in 440 to house a crèche which faithfully reproduced the one in Bethlehem.
The celebration of mass at midnight at Santa Maria Maggiore is based on the ancient belief that Jesus was born precisely on the stroke of twelve. We owe this to the XIIIth century Hungarian Saint Elizabeth. A IVth century Latin hymn, Quando noctis medium, already reflected the belief that the Messiah was born on the stroke of midnight.
Solemn and impressive with the happy sound of pealing bells, with light sparkling everywhere and with hymns of joy, Midnight Mass reached its high point with the procession of the Christ Child. Some Quebec churches have preserved this custom today, sometimes even conferring on a young couple and their baby the privilege of representing the Holy Family.