Antoinette d'Orléans Longueville was born in 1572 at the Château de Trie, near Gisors. Her mother is a first cousin of Ėléonore de Bourbon, Abbess of Fontevraud, and Antoine de Bourbon, father of Henri IV. At the age of 16 she was to marry Charles de Gondi, Marquis de Belle-Isle, a young Lord of 19. They spent two years at the Court of Henri III, but retired to the Château de Machecoul after the King's assassination. The couple had two sons, and after 12 years of marriage, tragedy struck in 1596 when the Marquis was killed while preparing to storm Mount Saint Michel.
The ordeal was hard and after settling her husband's affairs, Antoinette thought of answering the Lord's call, entrusting her children to their grandparents. On 23 October 1599, she entered the Feuillantines in Toulouse to lead a hidden life and "embrace the Cross of my God". On 31 October, at the age of 27, she received the habit and the name of Sister Antoinette of Saint Scholastica. In 1604 she was unanimously elected Prioress. After the disasters of the Wars of Religion, the situation in the Order of Fontevraud was grave. Abbess Éléonore de Bourbon, aunt of King Henri IV, did her utmost to re-establish the observance, initially with regard to communal life, but she was already elderly and felt the need for help. She thought of her niece, who had joined the Feuillantines in Toulouse. Éléonore de Bourbon applied to the Pope for a Brief which, on pain of excommunication, ordered Madame d'Orléans to leave the Feuillantines and go to Fontevraud, with the choice of becoming the Abbess's Grand Vicar for a year or exercising the office of coadjutress while keeping the habit of the Feuillantines. Madame d'Orléans arrived at Fontevraud on 25 October 1606.
In 1617, she founded a new religious order in Poitiers, the Congregation of the Benedictine Sisters of Our Lady of Calvary. She died 6 monts after its foundation.