Sonny Barger, founder of the Oakland chapter of the Hells Angels and the public face for the motorcycle club in the aftermath of the Altamont tragedy, has died at the age of 83.

Barger’s former attorney Fritz Clapp confirmed to NBC News that the longtime Hells Angels president died at his home Wednesday following a bout with liver cancer. Barger himself announced his own death Wednesday in a pre-written statement posted on his public Facebook page.

“If you are reading this message, you’ll know that I’m gone. I’ve asked that this note be posted immediately after my passing,” Barger wrote. “I’ve lived a long and good life filled with adventure. And I’ve had the privilege to be part of an amazing club. Although I’ve had a public persona for decades, I’ve mostly enjoyed special time with my club brothers, my family, and close friends.”

Barger continued, “Keep your head up high, stay loyal, remain free, and always value honor.” He signed the note, “Sonny HAMCO,” a nod to the Hells Angels Motorcycle Club Oakland that he founded in 1957.

Operating first on the fringes of society in the late-Fifties to mid-Sixties — a period where the motorcycle club was heavily involved in drug trafficking and grew infamous for their violent clashes with everyone from police officers to anti-war protestors (“peace creeps,” Barger called them) — the Hells Angels gained prominence in 1967 following the publication of Hunter S. Thompson’s first foray into gonzo journalism, Hell’s Angels: The Strange and Terrible Saga of the Outlaw Motorcycle Gangs.

“I don’t think Hunter ever tried to act like one of us. He always knew that he was apart from us. Some people get into thinking they’re one of us, and they really run into problems,” Barger told Rolling Stone in 2007. 

Ralph Hubert Barger, or “Sonny,” featured prominently throughout the book, which documented Thompson’s yearlong experience living among the bikers. Even though the book captured incidents of violence and sexual assault, it still managed to make the outlaw motorcycle gang lifestyle seem “glamorous” — “He made us even more of a myth than we were at the time,” Barger told Rolling Stone. The tome led to increased popularity in the club and Barger, who served as a technical consultant on films like Hells Angels on Wheels and Hell’s Angels ’69 soon after publication.

However, the cultural appeal was short-lived: On December 6th, 1969, the Hells Angels were at the epicenter of a violent confrontation between the biker gang — who were serving as unofficial security for the show — and concertgoers at the Rolling Stones’ Altamont Free Concert, resulting in the stabbing death of audience member Meredith Hunter by a member of the Hells Angels. Hunter allegedly pulled a gun on one of the Hells Angels, Barger would claim. The incident was captured in the documentary Gimme Shelter.

Barger insisted that the tragedy only occurred after the crowd started vandalizing the club’s motorcycles. “I don’t wanna do it, man, but I’m a violent cat,” Barger said. “I ain’t no cop. I ain’t never gonna police nothin’. I just went there to sit on the front of the stage and drink beer and have a good time, like we was told. But when they started kickin’ our bikes, man, that started it.”

“Mick Jagger used us for dupes, man,” Barger complained after the incident. “We were the biggest suckers for that idiot that I ever can see.”

Soon after, the law caught up to the Hells Angels and especially Barger, who faced charges ranging from drug-running to kidnapping to attempted murder. In 1973, after largely avoiding jail for the previous incidents, Barger was convicted on a narcotics charge, resulting in a nearly five-year prison sentence. 

Following his release, Barger returned to his post at the head of the Hells Angels and continued to ride into legal trouble, including a 1987 arrest where he and 13 other club members were hit with narcotics, weapons, conspiracy and explosives charges. Barger spent another four years behind bars and was released in 1992.

Over the past few decades, while still associated with the Hells Angels, Barger continued to find himself in headlines for more legal trouble, but also for his work as an author — he penned at least six books on the subject of motorcycling, including his tome Hell’s Angel: The Life and Times of Sonny Barger and the Hell’s Angels Motorcycle Club. He was also a recurring actor on Sons of Anarchy, a series based on the exploits of outlaw biker gangs.

“I’ve said it before and I’ll say it again,” Barger once told an interviewer according to Rolling Stone’s 1972 dive into the Hells Angels’ legal problems. “I’m gonna live in the world I want to live in. You people who run things ain’t got nothin’ to be proud of, you’ve left things in one hell of a mess.”