Dedication of Saint Mary Major

The Dedication of the Basilica of St Mary Major (In Dedicatione basilicae S. Mariae) is a feast day in the General Roman Calendar, optionally celebrated annually on 5 August with the rank of memorial.

In earlier editions of the General Roman Calendar, down to that of 1960, it is called the Dedication of the Basilica of St Mary of the Snows (In Dedicatione basilicae S. Mariae ad Nives), a reference to the legendary story about the foundation of the basilica. For the same reason the feast is also known popularly as Our Lady of the Snows. The reference to the legend was removed in the 1969 revision of the General Roman Calendar.

Pope Pius V inserted this feast into the General Roman Calendar in 1568, when, in response to the request of the Council of Trent, he reformed the Roman Breviary. Before that, it had been celebrated at first only in the church itself and, beginning in the 14th century, in all the churches of the city of Rome.

Accordingly, it appears in the Tridentine Calendar for celebration as a Double. In Pope Clement VIII's Missal of 1604, it was given the newly invented rank of Greater Double. In Pope John XXIII's 1960 calendar, it became a Third-Class Feast. This 1960 calendar, included in the 1962 edition of the Roman Missal, is the calendar whose continued use privately and, under certain conditions, publicly is authorized by the motu proprio Summorum Pontificum. Nine years later, the celebration became an optional memorial.

The feast commemorates the dedication by Pope Sixtus III of the rebuilt Basilica di Santa Maria Maggiore just after the First Council of Ephesus. This major basilica, located on the summit of the Esquiline Hill in Rome, is called the Basilica of Santa Maria Maggiore (Latin: Basilica Sanctae Mariae Maioris) because it is the largest church in Rome dedicated to the Blessed Virgin Mary.

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