The devotion of the Miraculous Medal owes its origin to Sister Catherine Laboré (Note: She was  subsequently canonized), a member of the Daughters of Charity of St. Vincent de Paul, to whom the Blessed Virgin Mary appeared three separate times in the year 1830, at the mother-house of  the community at Paris. The first of these apparitions occurred July 18, the 2nd November 27,  and the 3rd a short time later. On the second occasion, Sister Catherine records that the Blessed Virgin appeared as if standing on a globe, and bearing a globe in her hands. As if from rings set with precious stone s dazzling rays of light were  emitted from her fingers. These, she said, were symbols of the graces which would be bestowed on all who asked for  them. Sister Catherine adds that around the figure appeared an oval frame bearing in golden letters the words “O Mary, conceived without sin, pray for us who have recourse to thee”; on the back appeared the letter M,  surmounted by a cross, with a crossbar beneath it, and  under all the Sacred Hearts of Jesus and Mary, the  former surrounded by a crown of thorns, and the latter  pierced by a sword.

At the 2nd and 3rd of these visions a command was given to have a medal struck after the model revealed, and a  promise of great graces was made to those who wear it when blessed. After careful investigation,  M. Aladel, the spiritual director of Sister Catherine, obtained approval and on June 30, 1832, the  first medals were struck and with their distribution the devotion spread rapidly.

In 1847, M. Etienne, superior-general of the Congregation of the Mission, obtained from Pope Pius IX the privilege of establishing in the schools of the Sisters of Charity a confraternity under  the title of the Immaculate Conception, with all the indulgences attached to a similar society established for its students at Rome by the Society of Jesus. This confraternity adopted the Miraculous Medal as its badge, and the members known as the Children of Mary, wear it  attached to a blue ribbon.

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