In a growing city rich in history, pieces of the past inevitably get paved over. In Charleston, South Carolina, those pieces were often the graves of the poor, the black, and the enslaved. Now community activists and scientists are banding together to solve an archaeological mystery and right a historical wrong that lay buried for centuries.

In 2013, during a $142-million project to replace the city’s antiquated performing arts center, workers unearthed human bones near the rear of the building along Anson Street. After the coroner ruled out foul play, archaeologists carefully removed the remains of 36 individuals ranging from infants to adults older than 40.

Isotope analysis of their bones and teeth indicated that all of the dead were of