Reverend Louis William Dubourg, S.S., (1766-1833) had desired to expand educational programs for girls in Baltimore since 1797. He met Elizabeth Bayley Seton about 1806 in New York and invited her to that city where she served for one year as school mistress. She established (1808) a small boarding school for girls beside the Sulpician institution Saint Mary's College & Seminary on Paca Street. This plan enjoyed the enthusiastic support of John Carroll (1735-1815), first bishop of the United States and first archbishop of Baltimore (1789-1815). Carroll's primary concern was to provide educational opportunities for lay leaders and to develop native clergy for the Catholic Church in America

The Sulpician priests of Baltimore offered to assist Elizabeth in formulating plans that would be beneficial to the welfare of her children. They expected women to join Elizabeth in forming a sisterhood modeled on the French Daughters of Charity under their direction. Elizabeth entrusted such a project to Divine Providence. In a letter of February 20, 1809, to Rose Stubbs of New York, Elizabeth explained that she would be forming apostolic women who “choose to lead a Religious life devoted to the education of poor children in the Catholic faith . . . [with] the prospect of receiving many [spiritual] daughters.” Describing her vision of mission to Julia Sitgreaves Scott of Philadelphia in a letter dated March 23, 1809, Elizabeth exclaimed enthusiastically about “the joy” of her “soul at the prospect of being able to assist the Poor, visit the sick, comfort the sorrowful, clothe little innocents, and teach them to love God!” Two days later on March 25 Elizabeth pronounced vows of chastity and obedience to Bishop Carroll for one year in the lower chapel at Saint Mary's after which the Archbishop bestowed the title “Mother” on her. 

Graced with unswerving faith, Mother Seton remained undaunted by difficulties and challenges in her pioneer role in the American Church. Many trials were unsettling to the new community in its first years, including abrupt changes in Sulpician superiors, decisions about its model of government and relationship to the French Daughters of Charity, and determinations about a rule of life. 

 Under the guidance of Archbishop Carroll and the Sulpicians, Mother Seton and the early members of the Sisters of Charity of Saint Joseph's shaped the first native sisterhood in the United States, creating a truly American community. Despite their humble beginning, the American Sisters of Charity launched multi-faceted ministries and became trailblazers in many fields, especially in education. They established the first free Catholic school for girls staffed by sisters in the United States (Emmitsburg, 1810). As the prototype of the Catholic school, Saint Joseph's Academy and Day School laid the foundation for a national network of quality Catholic education through the parochial school system, which developed later in the century. After Mother Seton's death the Sisters of Charity of Saint Joseph's also began the first Catholic hospital in the United States (Saint Louis, 1828).