"Towards the break of day June 6, iconic music legend Malcolm John Rebennack, Jr., known as Dr. John, passed away of a heart attack," a statement on his social media pages said on Thursday.

Rebennack had already tallied more than a decade of experience as a session musician in his hometown and Los Angeles when he rose to solo fame in the late '60s after concocting his voodoo-influenced, patois-laced persona of "the Night Tripper."

In their history of postwar New Orleans music "Up From the Cradle of Jazz," Jason Berry, Jonathan Foose and Tad Jones wrote richly of the artist they called "a true original."

The writers described him exclamatorily: "Dr. John! - sunglasses and radiant colours, feathers and plumes, bones and beads around his neck, the crusty blues voice rich in dialect cadences, and then the man himself in motion: scattering glitter to the crowds, pumping the keyboard, a human carnival to behold."

After flashing his fantastical character on a quartet of early albums that garnered him an enthusiastic underground following, Dr. John settled in to become New Orleans' great latter-day exponent of bayou funk and jazz, playing in a style that reconciled the diverse streams of the city's music.

His early '70s work was distinguished by a collection of historic New Orleans favourites, "Gumbo," and a pair of albums with famed New Orleans producer-arranger-songwriter Allen Toussaint and funk quartet the Meters - the first of which, "In the Right Place," spawned a top-10 hit.

He memorably branched into traditional pop with his 1989 album "In a Sentimental Mood"; the album spawned the first of his six Grammy Awards, for "Makin' Whoopee," a duet with Ricki Lee Jones.

Dr John would delve deeper into jazz terrain later in his peripatetic career with Bluesiana Triangle, a collaboration with saxophonist David "Fathead" Newman and drummer Art Blakey, and homages to Duke Ellington and Louis Armstrong.

In 2008, his Grammy-winning collection "City That Care Forgot" dwelled movingly on the havoc wreaked on his city by 2005's Hurricane Katrina.

As an in-demand sideman, he recorded with Levon Helm, Gregg Allman, Van Morrison, Harry Connick, Jr, Ringo Starr and B.B. King, among others. He released "Triumvirate," a "super session" date with guitarists Mike Bloomfield and John Hammond, Jr, in 1973.

His turns on the big screen ranged from a memorable performance in Martin Scorsese's documentary about the Band's farewell performance The Last Waltz (1978) to an appearance as a member of the fictional "Louisiana Gator Boys" in Blues Brothers 2000 (1998).

He was inducted into the Rock and Roll Hall of Fame in 2011.

He was born Malcolm John "Mac" Rebennack, Jr, in New Orleans on November 21, 1941. He acquired a guitar as an adolescent and it became his principal instrument during his early professional career.

By the time he dropped out of Jesuit High School in the 11th grade, he had already acquired a taste for heroin and the chops to work as a session guitarist at Cosimo Matassa's studio J&M Music.

He recorded steadily, appearing on local hits by Jerry Byrne ("Lights Out") and Roland Stone ("Down the Road," aka "Junko Partner") and as a leader (including the 1959 instrumental "Storm Warning").

On Christmas Eve 1961 on a tour stop in Jacksonville, Florida, Rebennack and pianist Ronnie Barron got involved in a scuffle with a motel owner, and the guitarist was shot, nearly severing the ring finger on his fretting hand. During a slow recovery, he moved first to bass, and later to keyboards.

The studio scene in New Orleans was beginning to dry up in the early '60s when Rebennack was busted for heroin possession, drawing a two-year sentence in federal prison in Texas.

On his release from jail in 1965, he headed to Los Angeles, where a group of New Orleans expatriates that included producer-arranger Harold Battiste had set up shop as studio musicians. He worked with, among others, Canned Heat, the Mothers of Invention and Sonny & Cher.

Using studio time left over from a Sonny & Cher session, Rebennack and Battiste cut an album of hazy, incantatory songs steeped in Crescent City voodoo imagery. Issued by Atlantic Records' Atco subsidiary as "Gris-Gris," the collection failed to chart, but it inaugurated years of extroverted live shows that established Dr John as a unique under-the-radar performer.

Three more similarly styled albums - "Babylon" (1969), "Remedies" (1970) and "The Sun Moon and Herbs" (1971) - deepened the Dr John image; the latter album, recorded in London, included guest appearances by Eric Clapton and Mick Jagger.

However, he turned away from his original swampy style for an album he described in the notes as "More Gumbo, Less Gris Gris."

His first set with Toussaint and the Meters became his biggest commercial success: "In the Right Place" (No. 24, 1973) included the No. 9 single "Right Place Wrong Time."

In 1989, he landed at Warner Bros. Records with "In a Sentimental Mood," a well-received set of standards elegantly produced by Tommy LiPuma that included the Grammy-winning duet with Jones. That year, he finally kicked his more than three-decade addiction to heroin. Another Grammy winner, the self-descriptive "Goin' Back to New Orleans," followed in 1992.

He abided as an "eminence gris-gris" for the remainder of his career. He settled in for a long stay at Blue Note Records in the new millennium; his five-album sojourn for the imprint was inaugurated the Ellington tribute "Duke Elegant" in 2000.

The intensely felt "City That Care Forgot" was succeeded by the atypical "Locked Down" for Nonesuch Records in 2012; the album, produced by Dan Auerbach of the Black Keys and eschewing pianistics for a tough hard rock-based sound, also collected a Grammy as best blues album.

Australian Associated Press