The house remained in the Russell family until 1857 when it was purchased by Robert Allston (1801-1864), a successful rice planter who lived in the mansion while he was governor of South Carolina. In 1870, his executors sold it to the Sisters of Our Lady of Mercy where it served as a boarding school from 1870 through 1905, upon which the mansion was converted back to a private residence by the Mullally and Pelzer families. In 1955, when it became apparent that the garden may be subdivided after the house had languished on the market for two years, the Historic Charleston Foundation was created to preserve the property. Within 30 days, the Foundation was able to raise the $65,000 needed to purchase the property, and opened the house for public tours soon after.