Dio’s debut single “Holy Diver” was originally intended to be a Black Sabbath song, said Ronnie James Dio’s widow. He had already formed the song when his first stint with Sabbath ended acrimoniously in 1982, and it became the title track of his new band’s debut album the following year.

“He had written ‘Holy Diver’ and ‘Don’t Talk to Strangers’ during the time he was in Black Sabbath, so they were supposed to be Sabbath songs,” Wendy Dio told Full Metal Jackie in an interview marking what would have been the singer’s 80th birthday. “When he left Sabbath, we had a solo deal for him, and he just [took] those songs and got the band together, wrote more songs and it came out. Everyone was blown away about the reception that we got and how great the album was and how it's stood [the test] of time. It'll be 40 years next year.”

She added that Dio didn't think about Holy Diver’s success, focusing instead on pursuing his creative ambitions. “Ronnie always did what he wanted to do,” she said. “He never listened to what the record label wanted or anyone else. He always stuck to his guns in making the album. He hoped it would be successful – none of us realized how successful it was going to be.”

Watch Dio’s 'Holy Diver' Video

In a separate interview with 101WRIF, Dio drummer Vinny Appice – who quit Sabbath at the same time as Dio – recalled that the singer already had the solo deal in place, and he intended to make a record featuring a range of guest stars. “But when Sabbath got a little bit crazy and he wasn't happy anymore, he decided, ‘I’m going to use that record deal to put a new band together,’” Appice said.

“He had some of the ‘Holy Diver’ riff, and we jammed on it, just Ronnie and I. He played guitar a little bit, bass and drums … then we started auditioning guitar players.” Appice added that "we had a clean slate because we weren't Black Sabbath anymore. This was a new band, and anything could go. You don’t have to worry about repeating something you did on the previous album or a song sounding too similar to the previous album. It was a clean slate, and we had a lot of fun making this record.”

Black Sabbath Albums Ranked

From Ozzy to Dio and beyond, we look at all of the band's studio LPs.