Still, the critics were not kind at first. Black Sabbath was dismissed by some as “Satanic claptrap” and worse.

“The worst of the counterculture on a plastic platter,” Robert Christgau, the “Dean of American Rock Critics,” wrote.

But as the 1960s gave way to the 1970s, a new generation of fans embraced Black Sabbath’s dark lyrics and sludgy sound, a new style of rock music that would become known as heavy metal.

“The mark of a great rock band is that X-factor that sets them apart from other bands,” Bruce Barber, a former radio jock who teaches at the University of New Haven. “Ozzy had that X-factor. And for many young people, Black Sabbath’s music, which emerged in the late 1960s and early 1970s as the Vietnam War was raging, spoke to the issues of that time.”

Mark Tavern, a music professor at the University of New Haven, said Osbourne’s distinctive voice had a lot to do with Black Sabbath’s success.

“His throaty delivery, reminiscent of old-time blues shouters, brings an unkempt directness to the genre, a literal devil-may-care approach to singing that allowed blues-based rock to morph into metal,” Tavern said. “At the same time, his raw, shrieking wail fit with the band’s guitar-driven approach and meshed with the dark sounds and emotions that fans were looking to connect with.”

“Technically speaking, he was a natural tenor with a good range and a powerful, focused voice,” Katherine Dacey, a professor at the Berklee College of Music, said before Osbourne’s death was announced. “That description doesn’t really do justice to his instrument or artistry, though, as he had one of those rare voices that’s immediately recognizable.”

Meanwhile, Osbourne embraced the sex, drugs and rock n’ roll lifestyle with a gusto that drew comparisons to another world-class partier, Rolling Stones guitarist Keith Richards, and alarmed his bandmates.

Osbourne’s uncanny ability to consume prodigious amounts of cocaine and liquor — and not die — would later lead scientists in 2011 to conclude that he was a “genetic mutant” whose body possessed a unique ability to absorb recreational drugs.

“I’ve always said that at the end of the world there will be roaches, Ozzy and Keith Richards,” Sharon Osbourne said at the time.

But, as Iommi admitted to The Guardian years later, Osbourne was out of control during his last years with Black Sabbath. After a string of disappointing albums, Osbourne was fired in 1979 and replaced by Ronnie James Dio.

Getting canned, however, didn’t end Osbourne’s career. Enter Sharon Levy, the daughter of Don Arden, the man who managed Black Sabbath.

Arden had pushed for Osbourne to be fired. But Sharon made rescuing Osbourne her mission, becoming his manager, lover and, eventually, his wife.

Under her guidance, Osbourne released a 1980 solo debut, “Blizzard of Ozz,” which went multiplatinum and produced the hit song “Crazy Train.” He followed up a year later with another huge hit, “Diary of a Madman,” backed by a talented band of musicians, including a guitar wunderkind named Randy Rhoads.

During the tour for the album, Rhoads and two other members of the entourage died in a plane crash after the pilot reportedly tried to “buzz” the bus on which Osbourne was sleeping.

Sharon Osbourne also helped her husband get Ozzfest off the ground, a wildly popular music festival that toured between 1996 and 2018, often headlined by Osbourne, that featured other established and fledgling heavy metal and hard rock acts.

Despite all his success, Osbourne — in the eyes of many in the public — continued to be the madman who outraged animal rights groups in 1982 by biting the head off a live bat during a concert in Des Moines, Iowa.

“I thought it was a rubber bat,” Osbourne said at the time. “I picked it up, put it in my mouth, crunched down, bit into it, being the clown that I am.”

That same year, Osbourne infuriated the state of Texas by urinating on the Alamo, a stunt that got him arrested.

There also was the time Osbourne reportedly snorted live ants instead of cocaine on a whim in a bizarre contest with his band’s opening act, Mötley Crüe.

“We were a wild young band, and he kind of took us under his wing,” Crüe’s Nikki Sixx told the New York Post. “We thought we could compete with that, but you can’t with Ozzy. He won.”

By the end of the ‘90s, Osbourne’s popularity was fading. So in 2002, Sharon Osbourne rebooted her husband’s career yet again — on the cable TV channel that had helped him become a solo star.

“The Osbournes,” the MTV reality show that followed the aging rocker and his family’s unlikely domesticity won him a new audience.

“The show introduced him to a whole other group of people who had heard of him and vaguely knew his music but really got to know him through that show,” said Robert Thompson, the director of the Bleier Center for Television and Popular Culture at Syracuse University.

It also made Osbourne an unlikely TV star and led to invitations to meet the likes of President George W. Bush and perform at Queen Elizabeth II’s jubilee in 2002. He, of course, played “Paranoid.”

Barber said he interviewed the Osbournes around that time. He said he arrived at what was then called the Parker Meridien Hotel in Manhattan expecting to find them “in a trashed room.”

“Instead, there he was with Sharon dressed in matching Parker Meridian bathrobes,” Barber said. “They were kind and polite. And I was struck by the juxtaposition between the ‘Prince of Darkness’ Ozzy that we all heard about and the Ozzy sipping tea with Sharon.”

Osbourne continued to rock and roll — even reuniting with the original Black Sabbath lineup (minus Ward) for several lucrative tours and the band’s only No. 1 album in the U.S., “13,” which was released in 2013.

Twelve-years later came word that Osbourne, Iommi, Butler and Ward were reuniting for the first time in 20 years for a final concert in July 2025. The show sold out almost immediately after the box office opened.

By then, Osbourne had garnered what he had been denied when he first started out — respect from music critics and other naysayers who underestimated him and Black Sabbath.

“In his earlier days, he was never going to be considered one of the great vocalists of all time, but his voice certainly fit the music he made,” heavy metal historian Eddie Trunk said. “He had his moments as a singer, but his biggest legacy is as a tremendous character, a tremendous entertainer, and a very likable — and sellable — figure.”

Osbourne is survived by his wife, Sharon, and six children — Jessica, Louis and Elliot from his first marriage to Thelma Riley, and Aimee, Kelly and Jack from his second marriage. He also leaves behind quite the legend — onstage and off.

In 2002, Osbourne told Rolling Stone magazine that he would like his my epitaph to read “just ‘Ozzy Osbourne, born 1948, died so-and-so’.”

“I’ve done a lot for a simple working-class guy,” Osbourne said. “I made a lot of people smile. I’ve also made a lot of people go, ‘Who the f— does this guy think he is?’ I guarantee that if I was to die tonight, tomorrow it would be, ‘Ozzy Osbourne, the man who bit the head off a bat, died in his hotel room … .’ I know that’s coming.

“But I’ve got no complaints. At least I’ll be remembered.”