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, is publicly 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 () because it is the largest church in Rome dedicated to the
Blessed Virgin Mary. The original church, which was replaced by that of Pope Sixtus III, was built during the pontificate of
Pope Liberius (352–366), and is thus sometimes known as the
Basilica Liberii or
Basilica Liberiana. == Legend ==