Celebrity has settled like a gentle cloak on Deacon John Moore, the supreme bandmaster of New Orleans R&B. One of the few musicians to perform at every single New Orleans Jazz & Heritage Festival since the first, in 1969, Moore gained a role in the debut season of Treme on HBO. He played music elder Danny Nelson, who struggles in the aftershocks of Katrina, mentor to the trombone-playing protagonist, Antoine Batiste (played by Wendell Pierce).

“It was my first opportunity at a speaking role,” he explains in the Uptown studio of his workhouse (next door to the “home-house”), a room filled with instruments, religious art and aging concert posters.

“I auditioned for a speaking role. To make myself become Danny Nelson I had to look depressed.” He pauses, his signature cheshire cat grin lighting up his face. “I didn’t know I was going to die. You sign a sworn statement; you can’t reveal to anyone what will happen [in the plot]. I was thrilled to work with these wonderful actors. Wendell Pierce went to school with my daughter. I played his father’s 80th birthday party.”

He found video afterlife in the role of himself in a TV spot for CapitalOne Bank, saying: “What’s in your wallet?”

 “Art Neville – he’s my neighbor – called the other night and asked about my wallet,” he laughs in a lilt.

Born John Moore in 1941, raised in a sprawling Creole family on the cusp of the 6th and 7th wards, he was playing with R&B bands at 16 and leading the Ivories at 18. “I’ve never had a day job since day one,” he confides. “I bought my first house at 22. I was making more money than my father.”

He got his stage name in rehearsals. “We had competition, like Sugar Boy and the Cane Cutters; and Tommy Ridgley and the Untouchables. One day, rehearsing at drummer Al Miller’s house, he said, ‘Let’s call him Deacon John!’ Oh man, I didn’t want that.” He glances at a framed photograph of the Virgin Mary. “The more I protested the more they laughed. They all voted for it – but me.”

Deacon John and the Ivories played a repertoire of Bobby Blue Bland, Bo Diddley, Chuck Berry and Fats Domino in a circuit of black clubs anchored by the Dew Drop. He was soon landing gigs at the Valencia youth club and white debutante parties, when the Beatles revolutionized American rock. As Deacon John broadened the songbag his bookings for white groups took off.

Still, he remembers segregated dressing rooms. He remembers a five-night-a-week gig at an Airline Highway club where the owner wouldn’t let his wife sit at the bar; he quit on the spot. As one of the first black students at LSUNO [now UNO] he remembers racist graffiti and white students sitting apart from blacks in the dining room.

As racial tensions eased, Deacon John and the Ivories found a rocking good budget from Carnival balls, and fraternity and debutante parties. The adage that “every generation stays loyal to the music of its youth,” translated into Moore’s livelihood. The teenagers whose parties he played grew up and hired him to play at weddings, balls and parties for their kids. No other New Orleans bandleader straddles as many generations or has such a diverse following.

No other musician with such enduring popularity plays so few public events. He rarely plays in nightclubs; they don’t pay a big band as well as the private gigs. Deacon John is scheduled for May 1 at Jazz Fest, May 8 at Sweet Lorraine’s and May 28 at Snug Harbor.

His repertoire, built on the music made popular by other artists, blunted his prospects as a recording artist. Without a stream of recordings under his own name, there was no place on the European summer concert circuit where many local artists thrive. He thrived in a different way. The big one came late.

In 2003, Baton Rouge producer Cyril Vetter and his daughter Gabrielle Vetter produced the CD Deacon John’s Jump Blues and a companion TV documentary, which showcased the man at his best, singing through the R&B hit parade. Deacon John’s Jump Blues ranks with The Wild Tchoupitoulas and the collected hits of Fats Domino and Professor Longhair as one of the best records of New Orleans popular music.

“Some ladies out there whose proms I played tell me they put Jump Blues on the car player when they drive the kids to school, and they say the kids are happy when they get out the door.” He smiles. “Baby, I was cross-cultural before rappers and hip-hoppers knew how to spell.”