Stories of Real Human Beings Make History Powerful. Photographs Make it Immediate- A Photo From “Envisioning Emancipation: Black Americans and the End of Slavery,” Created by Historians Deborah Willis and Barbara Krauthamer.

"We wanted to imagine what freedom looked like for these people," says Willis, a North Philly native, a professor of photography and imaging at New York University, and a leading curator of African American images. "The people saving their money, going to a photographer’s studio, getting dressed and forming a biography - remaining themselves as free people."

The two men were soldiers from Wisconsin’s 22d Infantry Regiment, and they were escorting the escaped teenage slave - who had disguised herself as a boy - from Kentucky to Cincinnati in 1862. They’d been assigned to take her to an Underground Railroad safe haven. The photographer and abolitionist J.P. Ball posed the soldiers to hold their pistols high, symbolizing bravery in protecting their young charge.

"The images allowed us to show [African Americans] in a way that written sources don’t yield that same kind of complexity," says Krauthamer, a professor of history at the University of Massachusetts. "When you see a picture of a washerwoman slave who got herself in the Union army, earned her freedom, and was part of the war effort, that’s deep."