Saint Louise de Marillac was born in France, but lost her mother when she was still a child, and then her beloved father when she was 15. She desired to become a nun, but was discouraged by her confessor. So, she was married and had one son. However, Louise soon was nursing her beloved husband through a protracted illness in which he finally died.

Louise was lucky to have a wise counselor Francis de Sales. However, there was to be an even more powerful figure in her life. This was the priest Monsieur Vincent, later known as Saint Vincent de Paul. Initially, he was reluctant to be her confessor, since he was busy with his Confraternities of Charity - a collection of aristocratic ladies of charity who helped him nurse the poor and look after neglected children, a real need of the day. But the ladies were busy with their own concerns. He needed help.

After becoming acquainted with Louise, St. Vincent realized that she was the answer to his prayers. She was intelligent, self-effacing, and had endurance. The missions he sent her on led to four other simple young women joining her efforts. Her rented home in Paris became a training center for those willing to help the sick and poor.

The community grew quickly, and soon, they needed a "rule of life", which, under the guidance of St. Vincent, was put together for the Daughters of Charity of St. Vincent de Paul. This was eventually approved by Rome.   

Many of the young women under her care were illiterate, but this did not stop the new community from undertaking the care of neglected children. Louise busied herself helping whoever had need, despite her poor health. She traveled all over France, establishing her community members in hospitals, orphanages, and elsewhere. At the time of her death - March 15, 1660 - the congregation had over 40 houses in France. Louise de Marillac was canonized in 1934.