While attending the first Provincial Council of Baltimore in the fall of 1829, Bishop John England of Charleston, SC met four women of that city: sisters Mary and Honora O’Gorman, their niece, Teresa Barry (aged 15), natives of Ireland and Mary Elizabeth Burke, who all wished to live a consecrated life dedicated to serving the poor, sick, orphaned and uneducated in his diocese. England accepted their offer and had them sail with him on his return to Charleston, where they landed on the following November 23rd. He established them as a religious community on December 8th. He called the new community the Sisters of Our Lady of Mercy and patterned it after the Sisters of Charity founded by Mother Elizabeth Ann Seton in Emmitsburg, Maryland.
The Sisters quickly opened a school in their residence, which later moved to a larger site, where they established a school, orphanage and convent. They received incorporation by the State of South Carolina in 1835. They operated a number of educational and medical institutions which lasted for varying periods, including a school for the children of free blacks.
The Constitutions of the infant congregation were written by the second Bishop of Charleston, Ignatius A. Reynolds, in 1844. He based the Constitutions on those of the Sisters of Charity of Nazareth, whom he knew as a native of Kentucky, and on the simple Rule given to the Sisters by England, which was based on the Rule of Life of St. Vincent de Paul.
In the mid-19th century, even through the turmoil of the American Civil War, the congregation grew and expanded into the states of Georgia and North Carolina.
In 1882 the Sisters opened St. Francis Xavier Hospital, which exists today as Bon Secours St. Francis Hospital in Charleston. They cared for soldiers wounded in the Spanish-American War and for yellow fever victims. The Sisters also responded to the increasing need for trained nurses by establishing the St. Francis Xavier Infirmary Training School for Nurses which opened on October 22, 1900.
In 1949, the congregation adopted a new Constitution and a new name: the Sisters of Charity of Our Lady of Mercy. The Community joined the Sisters of Charity Federation in 1994.
In 1989 the Congregation transferred sponsorship of its hospitals to the Bon Secours Hospital System and established an Outreach Facility providing direct service to the poor and elderly on Johns Island, James Island and Wadmalaw Island. Sisters also serve in the diocesan parochial schools, various parish ministries, and ministries of spiritual direction and pastoral counseling. As of 2014 fifteen Sisters of Charity of Our Lady of Mercy serve Charleston, South Carolina from the May Forrest motherhouse on James Island.