“The slaver is a ghost ship sailing on the edges of modern consciousness,” Marcus Rediker writes in his harrowing history “The Slave Ship.” The vessels were floating torture chambers that devoured more than twelve million lives, and their finely calibrated cruelties—lightless holds fetid with vomit and excrement, sick people bound to anchor chains and thrown en masse to waiting sharks—fuelled the global economy for half a millennium. They left a psychic imprint so deep that Black people still speak of them in terms of personal experience. “I remember on the slave ship, how they brutalized our very souls,” Bob Marley sings in “Slave Driver.”
One might have assumed that a handful of these vessels, at least eight hundred of which are known to have wrecked, would have turned up long ago. But those equipped to search for them have lacked incentives to do so. In 1972, commercial treasure hunters stumbled on the wreck of the Henrietta Marie, an English ship that sank near the Florida Keys after a slaving voyage—and moved on as soon as they realized that it wasn’t the Spanish galleon they were seeking. (It was later excavated.) Maritime archeologists, meanwhile, largely ignored the Middle Passage. Stephen Lubkemann, a professor at George Washington University, told me, “There were more archeological studies of cogs in bogs in Ireland than of slave ships.”
Lubkemann conceived of the S.W.P. in 2003. Slavery wasn’t his field, but he’d long marvelled that historians, who’d recently unveiled the monumental Trans-Atlantic Slave Trade Database, were so far ahead of his social-science peers. Because of its expense, maritime archeology is reliant on funding from governments, few of which wanted to pay for the exposure of their historical crimes. An exception was post-apartheid South Africa, where Jaco Boshoff, a researcher at the Iziko Museums, was looking for a Dutch slaver called the Meermin. He and Lubkemann joined forces and expanded the search to other ships, shuttling between nautical archives and Cape Town’s wreck-strewn littoral.
For years, both dollars and discoveries eluded them. Then, in 2008, Boshoff encountered a scholarly citation about a Portuguese ship that sank en route from Mozambique to Brazil, carrying two hundred Africans to their deaths. Further research led to the captain’s testimony, which indicated a spot under a mountain known as Lion’s Head. Soon, Boshoff and his team were diving at what he called “one of the worst wreck sites I’ve ever worked on.” The archeologists were dashed against the very reefs that had sunk the vessel; one almost drowned. Still worse, the wreck was itself a wreck, having already been stripped by treasure hunters in the nineteen-eighties. (They found human remains, which have since disappeared.) Just enough remained to identify the vessel: crumpled copper sheathing from the period; iron ballast blocks that were mentioned in the manifest; and, most crucially, timber from a tropical hardwood that grew in Mozambique. By 2015, Boshoff and Lubkemann were confident enough to announce that they’d found the São José—the first known wreck of a ship that sank during a slaving voyage.