Historians lauded the discovery as a crucial missing piece of the broader American story. In Africatown, a semi-isolated clutch of cottages three miles north of downtown Mobile, the news carried a particular kind of heft. Something physical, something measurable, was now attached to the tale they had heard all their lives.

“Now it’s like letting us know that it’s really real,” said Ms. Harris, 58. “It’s real.”

While it is too soon to say whether the Clotilda will be raised or restored — and if it is, where exactly it will go — the people of Africatown are already dreaming that the ship’s bones will reside with them, serving as a key not only to the past but to the future, attracting tourists and sparking a much-needed renaissance.

“We think it could be something like Jamestown,” said Joe Womack, 68, referring to the early colonial settlement and tourist draw in Virginia. “Jamestown and Africatown.”

The story of the Clotilda’s final voyage began with an Alabama plantation and steamboat owner, Timothy Meaher. As tensions between North and South approached a breaking point before the Civil War, Mr. Meaher made a wager that he could bring enslaved Africans to the heart of American cotton country despite a federal ban on importation that had been in effect since 1808. The bet grew out of an argument among passengers on one of Mr. Meaher’s steamships over whether transporting enslaved people from Africa to the United States was still possible.