Mapping Mississippi's Violent Past - I wanted to understand the forces that shaped my state's dark history. I ended up in Spain, holding an object I'd never known existed.

I'd come researching my new book, The Barn, a history of the 36 square miles of dirt around the place where Emmett Till was tortured and killed in 1955. The barn, which I first wrote about for this magazine, sits in the southwestern quarter of Section 2, Township 22 North, Range 4 West, measured from the Choctaw Meridian. The township has been home to the civil-rights activist Fannie Lou Hamer; to the family of the Confederate general and early Ku Klux Klan leader Nathan Bedford Forrest; to farmland owned by James R. Binford, an original legal architect of Jim Crow.

- By Wright Thompson - Photographs by Laura León

The city of Seville awoke early, the old streets alive with singing birds and distant bells.

The cobblestone alleys smelled faintly of hidden gardens. I'd flown here for a chance to hold a 480-year-old map in my hand. The archive's curators had given me no guarantees but said that I could come, in person, to make the request. For a century after Christopher Columbus, this town was the white-hot center of global exploration, teeming with sailors who'd been to the New World and returned to tell the tale. Now it was mellow and quaint.

I'd come researching my new book, The Barn, a history of the 36 square miles of dirt around the place where Emmett Till was tortured and killed in 1955. The barn, which I first wrote about for this magazine, sits in the southwestern quarter of Section 2, Township 22 North, Range 4 West, measured from the Choctaw Meridian. The township has been home to the civil-rights activist Fannie Lou Hamer; to the family of the Confederate general and early Ku Klux Klan leader Nathan Bedford Forrest; to farmland owned by James R. Binford, an original legal architect of Jim Crow.

It's borne witness to the creation of the blues at Dockery Plantation; to the erasure of a Native American community; and, of course, to the death of Till. With so much violent history in such proximity, this project almost inevitably became a mapping. That led me on a hunt for the very first map of this land, which was likely drawn in 1544 by a Spanish cartographer named Alonso de Santa Cruz. (There had been earlier maps of the North American shoreline, but none of the interior until this one.)