Born as Ronald James Padavona in Cortland, NY, on July 10th 1942. Ronnie adopted the surname "Dio" sometime in the early '60's, taking inspiration from mobster Johnny Dio. He is considered one of the greatest heavy metal singers of all time and is known for his fantasy-based lyrics and "sword and sorcery" image.

Ronnie James Dio first began to gain national notice in the '70s when he fronted the rock group ELF (3), but his career stretched back to the mid '50s when he performed and recorded with local rockabilly, doo wop, and rock and roll groups in his native upstate New York (these recordings, some of which date to the late '50s, are now highly prized collector's items). Elf caught the attention of Deep Purple and the two groups toured together a number of times in the early '70s (Ian Paice and Roger Glover also produced Elf's debut LP). Ritchie Blackmore recruited most of Elf for his new band, Rainbow in 1975. Rainbow was the first time that Dio experienced some international stardom and also saw his first steps into the genre of heavy metal. In 1978, after 3 successful studio albums, Dio and Blackmore parted company when Blackmore decided to take Rainbow in a more commercial direction.

The following year, Ronnie joined Black Sabbath, who, at the time, were mired in a creative and commercial slump. The addition of Dio reinvigorated Black Sabbath and their first album together, 1980's "Heaven And Hell", became a major hit. The album allowed Dio to explore darker and heavier territories than he had been able to do in the past and is still cited by the singer as his favorite release of his career. Dio recorded another studio album with the band, but tensions ran high between Ronnie and Sabbath mainstays Tony Iommi and Geezer Butler. The situation dissolved completely during the mixing of the live album "Live Evil" (1982) and Dio departed the group, forming his own band, Dio (2) with Sabbath drummer Vinny Appice.

Dio experienced more success with 1983's "Holy Diver" and 1984's "Last in Line". By the beginning of the 1990s, though, both Black Sabbath's and Dio's careers were in commerical and critical decline. In 1992, Dio rejoined Black Sabbath to record the "Dehumanizer" album. By most accounts, the reunion was an uneasy one and Dio quit the group again when Tony Iommi and Geezer Butler agreed to open a show for original Sabbath frontman Ozzy Osbourne without consulting their current vocalist. Ronnie resurrected the Dio band and continued on with them for the rest of the decade and beyond.

In 2007, having put their animosities behind them, Iommi and Dio reunited to write three new tunes for a Dio-era Black Sabbath compilation that was being assembled by Rhino Records (2). This resulted in a reunion with Butler and Appice for the recording of the new songs and tour to celebrate the compilation's release. Deciding that they only wanted to focus on the Dio-era of the band, the quartet decided to tour under the name Heaven & Hell (2). The tour was such a success that Heaven & Hell decided to press forward with new material, recording and releasing a new studio album in 2009.

In late 2009, Ronnie was diagnosed with stomach cancer. On the morning of May 16th, 2010, Ronnie James Dio passed away due to complications to his disease.

He was married to Wendy Dio who also was his manager.

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