In 1808, the Unites States banned the importation of slaves, effectively putting an end to the transatlantic slave trade. Or so the history books have it, although the residents of Mobile, Ala.’s Africatown neighborhood know otherwise: Human trafficking continued for decades more. More than half a century later, in 1860, many of their ancestors were smuggled into the port city aboard a ship called the Clotilda by white men who’d wagered they could get away with it — and did, destroying the evidence. With no ship and no manifest, federal investigators dropped their case against the culprits, Timothy Meaher and Capt. William Foster, even though the proof was there all along, told and retold by the survivors and their families.

Director Margaret Brown honors those voices in her stunning Sundance-winning documentary “Descendant,” distinguishing between what passes for history (the version written by those in power) and the painful reality eyewitnesses have kept alive for generations via word of mouth. The film delves even deeper into many of the themes Brown explored in her extraordinary 2008 film “The Order of Myths,” about Mobile’s still-segregated Mardi Gras celebrations. Returning now as the wreck of the Clotilda is found, she observes how this bombshell discovery brings closure for some and a million questions for others.

America’s last known slave vessel was evidently the first to be located on U.S. soil. Finding it has enormous symbolic significance. In the time the ship was missing, it was possible for some to cast doubt on accounts told by the survivors. Worse still, according to local judge Karlos Finley, the liberated Africans and their kin were warned, “Do not repeat this story … because you could be killed, you could be lynched for making that accusation” — a chilling illustration of how the powers that be enforced their version of history in the Jim Crow South.

Brown, who is white, honors and amplifies work done decades earlier by the late Black author and filmmaker Zora Neale Hurston, whose book “Barracoon: The Story of the Last ‘Black Cargo’” focuses on Africatown founder (and Clotilda survivor) Cudjoe Lewis. Both Hurston — who recorded oral histories in the region — and Lewis serve as inspirations to Brown in her approach, which is deeply engaged with how to frame what happened and whose voices to center.

That’s a shifting and sometimes contradictory conversation, spanning everything from what a memorial might look like to talk of reparations. But Brown embraces the sheer complexity of the situation, much as she did in “The Order of Myths.” In that project, she explored the opposing forces of white supremacy and Black solidarity in Mobile’s still-segregated Mardi Gras celebrations. Here, she bears witness as those halves — descendants of both Lewis and Foster — come together for a moment of healing at the site where the Clotilda was found.

Absent from the conversation is the family of Timothy Meaher, who orchestrated the one-off smuggling mission, dividing the 110 souls the Clotilda carried between three plantations. The Meahers remain prominent members of the Mobile community — one even served as Mardi Gras queen in “The Order of Myths” — and recent documents reveal that while crews searched for the ship’s wreckage for years, the family was well aware of its whereabouts. Fresh forensic research suggests that someone even attempted to destroy what remained with dynamite. “I have a sense that this wreck has never been completely lost, at least to some,” says marine archaeologist Jim Delgado.

This past remains present, Brown shows, as activists explain how the land on which Africatown (formerly Magazine Point) was established once belonged to Meaher, who sold some of it to former slaves. But the family maintained control of the surrounding real estate, which was zoned for factories, whose polluting practices have been linked to high rates of cancer in the area. Talk of racial injustice calls for nuance, and it’s impressive just how many facets of the conversation Brown is able to include in her film.

The Meahers may be silent, but the director does speak to an older white neighbor, who is struggling to reconcile his personal values with the fact that his own family held slaves. “They don’t name schools after the losers’ generals, but in the South we do,” the man observes, attempting to untangle the “Lost Cause” mythology with which he was raised. For decades, the fallen Confederacy erected statues to its heroes — a handful of which Brown shows here.

As the descendants of the Clotilda strategize what a museum of their own might look like, Brown follows the organizers to similar sites in Montgomery and Washington, D.C. Turning Africatown into a tourist destination has drawbacks of its own, which a more inspiration-oriented helmer might have downplayed. Not Brown, who lets audiences make what they will of a rich tapestry. Consider the graveyard meeting between Emmett Lewis and a visiting historian, in which a direct descendant of Cudjoe’s chats with a white scholar of African American history. At long last, the survivors have a hand in the public narrative, thanks to Hurston’s efforts, the Clotilda’s discovery and Brown’s remarkable film.