The Basilica is sometimes referred to as Our Lady of the Snows, a name given to it in the Roman Missal from 1568 to 1969 in connection with the liturgical feast of the anniversary of its dedication on 5 August, a feast that was then denominated Dedicatio Sanctae Mariae ad Nives (Dedication of Saint Mary of the Snows). This name for the basilica had become popular in the 14th century[6] in connection with a legend that the 1911 Catholic Encyclopedia reports thus: "During the pontificate of Liberius, the Roman patrician John and his wife, who were without heirs, made a vow to donate their possessions to the Virgin Mary. They prayed that she might make known to them how they were to dispose of their property in her honour. On 5 August, at the height of the Roman summer, snow fell during the night on the summit of the Esquiline Hill. In obedience to a vision of the Virgin Mary which they had the same night, the couple built a basilica in honour of Mary on the very spot which was covered with snow. From the fact that no mention whatever is made of this alleged miracle until a few hundred years later, not even by Sixtus III in his eight-line dedicatory inscription ... it would seem that the legend has no historical basis."[7]
The legend is first reported only after AD 1000.[8] It may be implied in what the Liber Pontificalis, of the early 13th century, says of Pope Liberius: "He built the basilica of his own name (i.e. the Liberian Basilica) near the Macellum of Livia".[9] Its prevalence in the 15th century is shown in the painting of the Miracle of the Snow by Masolino da Panicale