NEW ORLEANS >> F. Brobson Lutz Jr. is one of those prominent Southern white men who once made a public appearance in blackface. It was at a big Mardi Gras parade years ago, and he knows there is photographic evidence.

And yet Lutz, a 71-year-old internist, is not in the least bit worried about any of it surfacing to embarrass him.

“I figure that since every black person of any prominence I knew was also in that parade” — and also in blackface, he said — “then I was in pretty good company.”

That parade was Zulu, famously staged each carnival morning by the historically African-American philanthropic and social club of the same name. Zulu’s paraders, mostly black but some of them white, wear blackface and grass skirts, a tradition that stems from a 1909 visit that club members made to a theater performance in which black people in blackface portrayed members of the southern African ethnic group.

This month, the revelation that Gov. Ralph Northam of Virginia and other white public figures once wore blackface has opened a conversation among New Orleanians about Zulu’s very different blackface tradition — about what it means, who should be allowed to participate, and whether it should continue.

The debate is as intense now as at any moment since midcentury, when some embarrassed black leaders urged the group to give up its costumes. In 1956, Clarence Laws, a former field secretary for the NAACP, called the parade “degrading and depressing,” and “perpetuating a stereotype which self-respecting Negroes detest.”

More than 60 years later, the tradition remains distasteful to some New Orleanians. “It’s always made me cringe,” wrote Jarvis DeBerry, a columnist with the Times-Picayune newspaper, earlier this month on Twitter. “That said, they swear it’s satire.”

Kim Coleman, 29, who like DeBerry is African-American, said this week that she no longer attended Zulu’s parade because of the sight of white people in blackface. “I find that disgusting,” said Coleman, curator of the city’s McKenna Museum of African-American Art.

This particular, and peculiar, blackface debate is at once familiar and different, whirled into some other thing by the complicated semiotic daiquiri machine that is New Orleans — and by the taboo-busting spirit of its carnival season. The pre-Lenten celebration of Mardi Gras, which this year falls on March 5, is a party that has long exposed the city’s serious social divisions, with its parading groups, or krewes, largely hewing to divides between black and white, suburbanite and city-dweller, old money and new.

But Mardi Gras is also about a radical suspension of seriousness. It was in that spirit that Sylvester Francis, 72, founder of the Backstreet Cultural Museum, which displays Mardi Gras Indian suits and other exuberant expressions of black Mardi Gras traditions, defended Zulu this week.

“It’s carnival. Do what you wanna. Be what you wanna,” said Francis, who is black.

“Even the governor,” he added, referring to Northam, “if he wants to wear blackface that one day, nobody would care.”

It was an intentional exaggeration, much like the Zulu costumes themselves. Members of the group and outsiders alike offer various opinions on their meaning and intent. In an interview Wednesday, Zulu’s historian emeritus, Clarence A. Becknell Sr., said the early paraders wore blackface because they were too poor to wear masks. “These people were laborers who started this organization — they couldn’t afford anything,” he said. “And blackface meant nothing.”

In a statement he issued Wednesday, Becknell urged people to not compare or conflate blackface with Zulu’s use of black makeup, calling the latter a way for the group to honor its African ancestry and the “continent’s most fierce warriors.”

There are other theories. Kim Vaz-Deville, an associate dean at Xavier University of Louisiana who has studied carnival, said that Zulu’s use of the black men wearing blackface is a satirical weapon subtly wielded against an exclusionary white society in the midst of the annual grand debauch.

Vaz-Deville said that it became unsafe for black residents to protest their condition after the 1896 Plessy v. Ferguson Supreme Court case that enshrined separate but equal accommodations for the races. (The case had been sparked by black New Orleanians testing segregated rail cars). Zulu, she argued, was a sendup of the whites-only carnival krewes that mimicked European royalty while upholding the segregated social order. Early kings wore a lard can for a crown and a banana stalk for a scepter.

“One of the ways that we found that people resist is through satire and irony and parody when they’re in oppressive situations, because it gives the cover of, ‘I’m making fun of you, but this is just a big joke in case you get angry,’” Vaz-Deville said. “They blackened their already-dark skin to say, ‘You white people are putting on white powder and coming from some mythical European space, so in the same way we’re going to darken our faces even more and say we come from a magical mystical place in Africa.”

Either way, the eventual inclusion of white people in Zulu, which Becknell said began in the late 1970s, amped up the complication.

For years, a New Orleanian who saw a white man in blackface on a Zulu float was likely to assume that the rider was either a member or an invited guest of a person of color. Instead of a boorish racist, that white person was likely to be perceived as a racial progressive, one who openly celebrated integration.

So it is with Lutz, who for 13 years served as the city health director and forged lasting friendships with black colleagues, one of whom sponsored him for membership in the mid-1980s. He is probably one of about 10 white men, out of 525 regular members, said Zulu’s president, Elroy James.

Earlier this week, Lutz stopped by the member’s lounge of Zulu Social Aid & Pleasure Club on North Broad Street, the only white face in a crowd of about 30 men. (The club is all-male, but women are involved in a number of its activities.)

He was immediately greeted with warm pats on the back and cries of “Doc!”

In a city over-blessed with good places to have a drink, the members-only Zulu lounge is among the best of them. There was a kind of eased-back, space-age funk on the sound system, the ambience was inviting and cheerful, and the back wall exploded with vibrant photos of Zulu kings past in spectacular glittering costumes. Some were in black face and some were not. Among them was Louis Armstrong, who reigned in 1949.

Most members hewed strictly to rules forbidding them to talk publicly about club business without the consent of the president. But a number of them said the blackface masking was purely positive — a way to honor tradition and the working men, locked out of white Mardi Gras, who had invented the practice long ago.

Later in the week in an interview, state Sen. Troy Carter, a Zulu member for two decades, said that the club’s blackface was in the spirit of African and Native American peoples who painted their faces as a matter of ritual or self-expression. “We’re paying homage to the original Zulu tribes of Africa,” he said.

But black paint on white faces has proved explosive when perceived beyond the membrane of New Orleans.

Coleman, the museum curator, said that her social media feeds had been blowing up with fresh debate over Zulu since Northam’s scandal. She used to attend the Zulu parade every year as a child, she said, but soured on it as she grew older and began questioning the world of New Orleans and her place in it.

She no longer attends. If white people ride on the floats, she said, they should wear a different uniform, no matter their views on race: It was “demeaning,” she said, to have to watch “a white man in black face throwing out coconuts,” a reference to the shaved and painted coconuts that are Zulu’s signature throw, and the most prized of the Mardi Gras loot that rains down from float-riders to spectators. (The coconuts are actually handed, not thrown, for insurance and safety reasons.)

Other black New Orleanians this week said they were as uncomfortable with Zulu’s presentation as the critics of the 1950s and ’60s. But they were reluctant to speak about it openly. The club, once the province of the working class, is today also stocked with local power brokers, doctors and lawyers, and generations of locals of all races find it difficult to conceive of Mardi Gras day without the spectacle Zulu provides.

It also remains a true social-aid organization, funding toy drives, food drives and scholarship programs.

Vaz-Deville predicted that the new debates would have little affect on the club, whose king proclaims each year that citizens shall endeavor to make merry and “not confuse Mardi Gras with other issues.”

“I think Zulu’s going to party like Zulu always parties,” she said.