Mary, by a unique divine privilege, was preserved from every stain of original sin. This belief was solemnly defined as a dogma of faith by Pope Pius IX on this very day in 1854.
The first traces of this feast are found in the East, around the 7th or 8th century. In the West, it first appeared in southern Italy, in regions then under Byzantine rule. The feast faced resistance before it became widespread: first, people questioned the feast itself; later, the exact object of the liturgical celebration was debated. Rome, cautious as usual, kept its reserve until 1476, when it finally included the feast in its own calendar.
The great solemnity with which the feast was later celebrated (a “double of the first class” with vigil) was due to Pope Leo XIII, who marked the 25th anniversary of the proclamation of the dogma in this way. Even after the liturgical reform of 1960, which simplified the categories of feasts, today’s calendar still honors December 8 as a solemnity.
