Many Christians, particularly those of Catholic faith, in Canada observe the Feast of the Immaculate Conception on or around December 8.

The Feast of the Immaculate Conception centers on the belief that Jesus’ mother, the Virgin Mary, was conceived without sin. Pope Pius IX issued an apostolic constitution, known as the Ineffabilis Deus, on December 8, 1854. This document clarified the importance of the Immaculate Conception in the Catholic Church.