Katrina Browne’s Traces of the Trade: A Story From the Deep North airs tonight at 9 on Channel 36.

The Providence Journal / Frieda Squires

Here’s a different way to kick off tomorrow’s Bristol Fourth of July Parade.

Tonight at 9, Channel 36 will present Katrina Browne’s documentary Traces of the Trade: A Story From the Deep North, about her ancestors’ — and Bristol’s — lucrative involvement in the slave trade in the 18th and 19th centuries.

Who knew that Bristol was the “historic center of the U.S. slave trade,” as Browne’s incisive, fascinating film tells us?

It’s a fact that’s deliberately glossed over in tours at Linden Place, which Browne says was built by her slaver ancestor George DeWolf. (Current board members wouldn’t allow her to film inside.) It’s hidden away in records filed in an upstairs corner of the Bristol Historical & Preservation Society. It’s a family history that wasn’t talked about openly even in Browne’s own family.

It wasn’t until her grandmother came clean in a DeWolf history booklet that prompted a lot of soul-searching by Browne. She wound up organizing a sort of family outing along the old Triangle Trade route that ran from Bristol to West Africa to Cuba, trading rum to African potentates who provided slaves to the DeWolf ships, which brought them to Cuba, where they worked in the sugar plantations to make the ingredients for rum.

Beginning in Bristol, Browne and nine of her relatives undertake a trek that includes visits to a slave fort in Ghana and the ruins of a sugar plantation in Cuba. Along the way there’s a lot of soul searching and breast beating by her highly educated family members, who pose intelligent questions about the past and worry about how to deal with their guilty feelings.

Traces of the Trade is filled with facts, quotes from diaries and ledgers that detail the roots — and the profits — of the trade.

One of the most interesting bits of information is how it wasn’t merely the DeWolf family, whose old warehouse at the water’s edge is now the site of offices and an upscale restaurant, who profited from the trade. The whole town of Bristol was complicit, Browne contends, in that there were shipbuilders and sailors and barrel makers and local merchants that made money off the slave trade.

Browne, who grew up in Philadelphia, invited more than 140 DeWolf descendants to join her. Of the nine who came along, one woman from Colorado recalls that a family rule was never to talk about unpleasant things and so the family’s slave dealings never surfaced.

At the start of the trip, a man from Oregon argues that this part of the family history took place a long, long time ago and existed in a context that was very different from our day. By the middle of the trip, however, after he has walked through the dungeon of a slave prison in Ghana, his tune has changed. Now he calls slavery “an evil thing and they knew it; it was an evil thing and they did it anyway.”

The trip to Ghana is an eye opener, especially when family members sit down with Africans to talk about history or when they attend a solemn ceremony commemorating the people who were taken away to be slaves in Cuba and South Carolina and even New England.

From Africa, the DeWolf descendants travel to Cuba to see the ruins of George DeWolf’s sugar plantation.

It’s a somber journey that brings them face to face with an unhappy past. And although Browne acknowledges that the money earned in the slave trade was frittered away long ago, the guilt remains that “money or no money, we’ve stayed in the elite.”

Some of that guilt gets washed away in a service at St. Michael’s Church in downtown Bristol where Browne delivers the homily in what turns into a healing service. It’s an uplifting moment in a touching — and touchy — film.

Funded by the Rhode Island Council for the Humanities, they plan to use the film as one of the jumping-off points in their recently launched “On the Road to Freedom” discussion series.

Following the 90-minute-long Traces of the Trade, which is being shown as part of PBS’s P.O.V. series, at 10:30 tonight (and 3 a.m. July 5) Channel 36 will present Telling Stories, a documentary about unearthing history in Rhode Island. It chronicles the Greene Farm Archaeology Project in Warwick, which focuses on researching 400 years of cultural and natural landscape transformations on one of the few remaining Providence plantations.

mjanuson@projo.com