Munificentissimus Deus () is the name of an apostolic constitution written by Pope Pius XII. It defines ex cathedra the dogma of the Assumption of the Blessed Virgin Mary. It was the first ex-cathedra infallible statement since the official ruling on papal infallibility was made at the First Vatican Council (1869–1870). In 1854 Pope Pius IX made an infallible statement with Ineffabilis Deus on the Immaculate Conception of the Virgin Mary, which was a basis for this dogma. The decree was promulgated on 1 November 1950. Dogma of the Assumption On 1 November 1950, invoking his dogmatic authority, Pope Pius XII defined the dogma: Historical background Pope Pius XII's previous encyclical (1 May 1946) to all Catholic bishops stated that for a long time past, numerous petitions had been received from cardinals, patriarchs, archbishops, bishops, priests, religious of both sexes, associations, universities and innumerable private persons, all begging that the bodily Assumption into heaven of the Blessed Virgin should be defined and proclaimed as a dogma of faith. This was also fervently requested by almost two hundred fathers in the Vatican Council (1869–1870). Following the example of Pope Pius IX, who canvassed Catholic bishops before proclaiming the dogma of the Immaculate Conception, Pius XII asked all bishops for their opinion. At issue was not the belief in the Assumption, but its dogmatisation. By August 1950, 1191 Bishops had responded. reports popular acclaim and "nearly unanimous" approval of the contemporary bishops. The names of the bishops attending the dogma celebration in 1950 are listed at the entrance of St. Peter's Basilica. Review of Catholic beliefs Reflecting on the history of this belief in Catholic Christian tradition, Pope Pius XII writes that "the holy Fathers and Doctors of the Church have never failed to draw enlightenment from this fact." reviews the history of Catholic liturgy and the many liturgical books "which deal with the feast either of the Dormition or of the Assumption of the Blessed Virgin". cites also the teaching of previous popes and bishops and such writers as John of Damascus, Francis de Sales, Robert Bellarmine, Anthony of Padua, and Albert the Great, among others. George Tavard wrote: "In the theology of Pope Pius XII, the Assumption of Mary's body and soul into heaven flow from her Immaculate Conception. The end balances the beginning, both having their profound reason in Mary's mission as the Theotokos." Relevance to the faithful Written