In 2007, while the restoration of James Madison’s Montpelier, in Orange, Va., was underway, a group of the estate’s African American stakeholders came to make a visit. Giles Morris, Montpelier’s vice president for marketing and communications, found himself on the terrace overlooking the South Lawn with Iris Ford, an associate professor of anthropology at St. Mary’s College of Maryland who is descended from people enslaved at Montpelier.

Ford wanted to know how much had been spent on the renovations to the main house. Her question called attention to the disparity between the attention lavished on the fourth president’s home and on the South Yard, where railroad ties marked the sites where an insurance map indicated that slave dwellings had stood. Weed killer had recently been sprayed on the area, and the ties rested on dead grass. The contrast between the grandeur of the South Terrace and the raw South Lawn was striking.

“It shames you, on some level,” Morris acknowledged when I visited Montpelier earlier in June.

Ten years later, and with the help of a $10 million gift from philanthropist David Rubenstein, the Montpelier staff has devoted new attention and resources to that untold story. The result is a series of reconstructed dwellings in the South Yard and a new permanent exhibit, “The Mere Distinction of Colour,” on the basement floor of Montpelier. The new galleries, which opened on June 5, do something radical: They treat the people who were enslaved at Montpelier as if their lives were as worthy of historical examination as that of the man who owned them.