The house is located on part of a 795-acre tract in Georgetown once own by Colonel Ninian Beall, a member of the Maryland House of Burgesses and Commander-in-Chief of Maryland's Provincial Forces from 1625 to 1717. Beall was one of the first settlers in the Georgetown area; he patented the tract as "The Rock of Dumbarton" in honor of the land of his birth in Scotland. The part of the land on which the mansion now stands remained in the Beall family until 1796, when the four and half-acre lot on which Dumbarton House was eventually erected was sold.
The Federal Government and its many civil servants moved to Washington in 1800, and the family of Joseph Nourse, the First Register of the United States Treasury, lived in the home from 1804-1814. Tradition has it that the next resident, Charles Carroll, a signer of the Declaration of Independence, sheltered the "President's Lady," Dolley Madison, in August 1814, when she was fleeing from the burning White House and invading British troops.
The National Society of Colonial Dames of America, a patriotic nonprofit organization founded in 1891 to collect and preserve objects of significant historical interest and to educate citizens about them, purchased the house in 1928 in order to preserve the mansion and adapt it for the organization's headquarters and as a house museum of early American architecture. The Colonial Dames renamed the property Dumbarton House after the original patent. In 1932, the organization embarked on an extensive restoration project to return the house to its original early Federal style. Two eminent professionals in the fields of architecture and landscape design, Fiske Kimball (1888-1955) and Horace Peaslee (1884-1959), directed the restoration of the property. Dumbarton House is still the headquarters of The National Society of the Colonial Dames of America. - NPS