The Smithsonian Castle was built in 1847. The historic structure sits in Washington D.C. and has recently been found to be built by slaves. Some of those slaves were owned by Martha Washington. There’s been a longtime search by historians to know which historic D.C. buildings were built by slaves. Two of the most notable buildings are the U.S. Capitol and the White House.
Anthropology professor Mark Auslander of Central Washington University discovered the building’s work order that listed “colored men” on the ledger. This was a common reference to slaves. Freed men would most likely have their names listed on the documents.
The castle, which was completed in 1855, was built with sandstone from the quarry owned by John Parke Custis Peter. Peter was the great-grandson of Martha Washington, the wife of President George Washington. Though the president himself relinquished his slaves, his wife kept her own, which were acquired through a prior marriage. Peter inherited his great-grandmother’s slaves.
Auslander traveled to Seneca, where the sandstone quarry was and spoke to the local black community to find answers. Though nothing was confirmed through interviews, the descendants of those who lived in the area passed along the stories they had heard about the slaves, the sandstone and the castle.