On the night of 18 July, 1830, a "child" awakened Sr. Catherine Labouré  (seen above) in her Sisters of Charity convent at 140 Rue du Bac, Paris, telling her to go to the convent's chapel where Mary awaited her. There Mary told her:

God wishes to charge you with a mission. You will be contradicted, but do not fear; you will have the grace. Tell your spiritual director all that passes within you. Times are evil in France and in the world. Come to the foot of the altar. Graces will be shed on all, great and little, especially upon those who seek them. Another community of sisters will join the Rue du Bac community. The community will become large; you will have the protection of God and Saint Vincent; I will always have my eyes upon you.

(Saint Elizabeth Seton sisters of Emmitsburg, MD later joined the community).

Later that year, on 27 November, Catherine saw another vision of Mary. She describes her like this:

Her height was medium and her countenance, indescribably beautiful. She was dressed in a robe the color of the dawn, high-necked, with plain sleeves. Her head was covered with a white veil, which floated over Her shoulders down to her feet. Her feet rested upon a globe, or rather one half of a globe, for that was all that could be seen. Her hands which were on a level with her waist, held in an easy manner another globe, a figure of the world. Her eyes were raised to Heaven, and her countenance beamed with light as She offered the globe to Our Lord.

Mary told her that the globe represented the whole world, especially France, a country whose faithful had recently suffered horrible persecutions in the Revolution's Terrors and was still going through "Enlightenment" perfidy.

The vision changed to Mary, still standing on a globe, rays of light streaming from her fingers, enframed in an oval frame inscribed with the words, "O Mary, conceived without sin, pray for us who have recourse to thee." The whole vision "turned" showing the back of the oval inscribed with the letter "M" entwined with a Cross, and the hearts of Jesus and Mary, the former surrounded with thorns, the latter pierced with a sword. 12 stars circled this oval frame, symbolizing the 12 Tribes of Israel and the 12 Apostles, and showing Mary as the Mother of Israel, per the Apocalypse (ch. 12). Mary told her to strike a medal in this form, and that all who wore it after having it blessed would receive graces.

Sr. Catherine's spiritual director told Catherine's story to the Bishop of Paris, who not only allowed the medal to be struck, but received some of them himself.  One of these he had with him when ministering to Napoleon's dying, heretical chaplain. The dying man had obstinately refused to reconcile with the Church, but as the Bishop was leaving after trying one last time to get him to see the error of his ways, the man suddenly broke down and repented. The Bishop attributed this to the Virgin's intercessions through the medal.

Another miraculous conversion involved that of a wealthy Jewish banker-lawyer named Alphonse Ratisbonne. He was actually dared to wear one of the medals and to pray the Memorare. This he did, and as he visited a church to arrange a funeral for a friend, he had a vision of Our Lady as she appears on the Medal. He instantly converted, and became a priest.

The Medal of the Immaculate Conception, now known as the Miraculous Medal, has become one of the most commonly worn sacramentals in the Roman Church.

St. Catherine Labouré's body remains incorrupt to this day and can be seen at her convent at Rue du Bac.

Note: St. Maximillian Kolbe (+ 1941) adopted the miraculous medal as the badge of the "Pious Union of the Militia of the Immaculate Conception" in 1917, which he founded in Rome while still a young religious of the Conventual Friars Minor

Novena and Prayers for the Miraculous Medal

 

Priest: In the name of the Father and of the Son and of the Holy Spirit.

People: Amen.

Priest: Come, O Holy Spirit, fill the hearts of Your Faithful, and kindle in them the fire of Your love.
Send forth Your Spirit, and they shall be created.

People: And You shall renew the face of the earth.

Priest: Let us pray.
Oh God who did instruct the hearts of the faithful by the light of the Holy Spirit, grant us in the same Spirit to be trulywise and ever to rejoice in His consolation, through Jesus Christ Our Lord.

People: Amen.

Priest: O Mary, conceived without sin.

People: Pray for us who have recourse to thee. (say three times)

Priest and People: O Lord Jesus Christ, who have vouchsafed to glorify by numberless miracles Blessed Virgin Mary, immaculate from the first moment of her conception, I grant that all who devoutly implore her protection on earth, may eternally enjoy Your presence in heaven, who, with the Father and Holy Spirit, live and reign, God, forever and ever. Amen.

 

O Lord Jesus Christ, who for the accomplishment of Your greatest works, have chosen the weak things of the world, that no flesh may glory in Your sight; and who for a better and more widely diffused belief in the Immaculate Conception of Your Mother, have wished that the Miraculous Medal be manifested to Saint Catherine Laboure, grant, we beseech You, that filled with like humility, we may glorify this mystery by word and work. Amen.

 

Memorare

Priest and People: Remember, O most compassionate Virgin Mary, that never was it known that anyone who fled to your protection, implored your assistance, or sought your intercession, was left unaided. Inspired with this confidence, we fly unto you, O Virgin of Virgins, our Mother; to you we come; before you we kneel sinful and sorrowful. O Mother of the Word Incarnate, despise not our petitions, but in your clemency hear and answer them. Amen.

 

Novena Prayer

Priest and People: O Immaculate Virgin Mary, Mother of Our Lord Jesus and our Mother, penetrated with the most lively confidence in your all-powerful and never-failing intercession, manifested so often through the Miraculous Medal, we your loving and trustful children implore you to obtain for us the graces and favors we ask during this Novena, if they be beneficial to our immortal souls, and the souls for whom we pray. (Here privately form your petitions.)

You know, O Mary, how often our souls have been the sanctuaries of your Son who hates iniquity. Obtain for us then a deep hatred of sin and that purity of heart which will attach us to God alone so that our every thought, word and deed may tend to His greater glory. Obtain for us also a spirit of prayer and self-denial that we may recover by penance what we have lost by sin and at length attain to that blessed abode where you are the Queen of angels and of men. Amen.