Assumption of the Blessed Virgin Mary, FEAST OF THE, 15, Aug.; also called in old liturgical books PAUSATIO, NATIVITAS (for heaven), MORS, DEPOSITIO, DORMITIO S. MARIÆ. This feast has a double object: (1) the happy departure of Mary from this life; (2) the assumption of her body into heaven. It is the principal feast of the Blessed Virgin.

    Regarding the origin of the feast we are also uncertain. It is more probably the anniversary of the dedication of some church than the actual anniversary of Our Lady's death. That it originated at the time of the Council of Ephesus, or that St. Damasus introduced it in Rome is only a hypothesis. According to the life of St. Theodosius (d. 529) it was celebrated in Palestine before the year 500, probably in August (Baeumer, Brevier, 185). In Egypt and Arabia, however, it was kept in January, and since the monks of Gaul adopted many usages from the Egyptian monks (Baeumer, Brevier, 163), we find this feast in Gaul in the sixth century, in January [mediante mense undecimo (Greg. Turon., De gloria mart., I, ix)]. The Gallican Liturgy has it on the 18th of January, under the title: Depositio, Assumptio, or Festivitas S. Mariæ (cf. the notes of Mabillon on the Gallican Liturgy, P. L., LXXII, 180). This custom was kept up in the Gallican Church to the time of the introduction of the Roman rite. In the Greek Church, it seems, some kept this feast in January, with the monks of Egypt; others in August, with those of Palestine; wherefore the Emperor Maurice (d. 602), if the account of the "Liber Pontificalis" (II, 508) be correct, set the feast for the Greek Empire on 15 August. In Rome (Batiffol, Brev. Rom., 134) the oldest and only feast of Our Lady was 1 January, the octave of Christ's birth. It was celebrated first at Santa Maria Maggiore, later at Santa Maria ad Martyres. The other feasts are of Byzantine origin. Duchesne thinks (Origines du culte chr., 262) that before the seventh century no other feast was kept at Rome, and that consequently the feast of the Assumption, found in the sacramentaries of Gelasius and Gregory, is a spurious addition made in the eighth or seventh century. Probst, however (Sacramentarien, 264 sqq.), brings forth good arguments to prove that the Mass of the Blessed Virgin Mary, found on the 15th of August in the Gelasianum, is genuine, since it does not mention the corporeal assumption of Mary; that, consequently, the feast was celebrated in the church of Santa Maria Maggiore at Rome at least in the sixth century. He proves, furthermore, that the Mass of the Gregorian Sacramentary, such as we have it, is of Gallican origin (since the belief in the bodily assumption of Mary, under the influence of the apocryphal writings, is older in Gaul than in Rome), and that it supplanted the old Gelasian Mass. At the time of Sergius I (700) this feast was one of the principal festivities in Rome; the procession started from the church of St. Hadrian. It was always a double of the first class and a Holy Day of obligation. The octave was added in 847 by Leo IV; in Germany this octave was not observed in several dioceses up to the time of the Reformation. The Church of Milan has not accepted it up to this day (Ordo Ambros., 1906). The octave is privileged in the dioceses of the provinces of Sienna, Fermo, Michoacan, etc. The Greek Church continues this feast to 23 August, inclusive, and in some monasteries of Mount Athos it is protracted to 29 August (Menaea Graeca, Venice, 1880), or was, at least, formerly. In the dioceses of Bavaria a thirtieth day (a species of month's mind) of the Assumption was celebrated during the Middle Ages, 13 Sept., with the Office of the Assumption (double); to-day, only the Diocese of Augsburg has retained this old custom. Some of the Bavarian dioceses and those of Brandenburg, Mainz, Frankfort, etc., on 23 Sept. kept the feast of the "Second Assumption", or the "Fortieth Day of the Assumption" (double) believing, according to the revelations of St. Elizabeth of Schönau (d. 1165) and of St. Bertrand, O.C. (d. 1170), that the B.V. Mary was taken up to heaven on the fortieth day after her death (Grotefend, Calendaria 2, 136). The Brigittines kept the feast of the "Glorification of Mary" (double) 30 Aug., since St. Brigitta of Sweden says (Revel., VI, l) that Mary was taken into heaven fifteen days after her departure (Colvenerius, Cal. Mar., 30 Aug.). In Central America a special feast of the Coronation of Mary in heaven (double major) is celebrated 18 Aug. The city of Gerace in Calabria keeps three successive days with the rite of a double first class, commemorating: 15th of August, the death of Mary; 16th of August, her Coronation. At Piazza, in Sicily, there is a commemoration of the Assumption of Mary (double second class) the 20th of February, the anniversary of the earthquake of 1743. A similar feast (double major with octave) is kept at Martano, Diocese of Otranto, in Apulia, 19th of November.

The Catholic Encyclopedia, Volume II, pp. 6-7
Imprimatur. +John M. Farley, Archbishop of New York