Bain was born in Newtonmore, Highland, in Scotland. Jimmy Bain played in several provincial amateur bands before emigrating to Vancouver with his parents. By his early twenties he was playing professionally in Street Noise. Returning to London, Bain joined Harlot in early 1974, after recently turning down a job with The Babys.
Bain was asked to join Rainbow after Ritchie Blackmore had caught a show at the Marquee. Jimmy would record Rising and play on the following world tour. In January 1977 Bain was sacked from the band.
In the early 1980s, Bain formed a band called Wild Horses with ex-Thin Lizzy guitarist Brian Robertson and included Clive Edwards and Neil Carter. Wild Horses released two albums on EMI, Wild Horses and Stand Your Ground, before Robertson left to join Motörhead.
Bain regrouped Wild Horses as a five piece but they disbanded shortly after. Jimmy then worked with the former Family main-man Roger Chapman, Roy Harper, Gary Moore and Kate Bush (on 1982’s The Dreaming). Jimmy co-wrote with his close friend Phil Lynott for the Lizzy man’s two solo albums. Not only a bassist but a very capable keyboard player, he toured the material playing keyboards with Phil’s band.
In 1983 Jimmy linked up again with ex-Rainbow vocalist Ronnie James Dio in his solo project. A central figure within Dio the band, Jimmy helped co-write some of the most successful heavy metal of the eighties.
Bain also played a central part in writing ‘Stars’, the Heavy Rock world’s contribution to the famine relief charity appeal started by Bob Geldof and Live Aid.
By 1989 Ronnie Dio dismissed the band. Jimmy’s personal circumstances were further complicated with his ongoing battle with alcohol and drug addiction.
He signed a solo deal with Atco Records in 1988, and employed Iron Maiden’s Bruce Dickinson and Quiet Riot drummer Frankie Banali on demo material of a more commercial nature than that attempted with Dio.
In autumn 1989. Jimmy formed a band with vocalist Mandy Lyon called World War III.
After their 1991 eponymous debut album. the band floundered.
By the mid-nineties Jimmy, now having thankfully conquered his addictions, had started work on a new venture. ‘The Key’ utilised a far more melodic and commercial approach. Guitarist on the project was Tracey G, borrowed from Dio’s then band who was also the guitarist for World War III.
Ronnie Dio’s concept project Magica saw the return of Jimmy Bain to the Dio story. Bain played on the albums Magica and Killing the Dragon. In the mid-'90s, Bain attempted to produce a solo album, to be named Bain, but the project was never completed.
In 2005. Bain joined up with former Black Sabbath and Dio band drummer Vinny Appice for two projects, The Hollywood Alstarz and 3 Legged Dogg. The first group produced live concerts that featured a greatest hits set of the individual members, (Carlos Cavazo of Quiet Riot was another notable in the band), while the second group produced a well received CD of original material. In an interview with noted journalist David Lee Wilson Bain lamented Appice's choice to put both these groups on hold while he toured with Ronnie James Dio in the Black Sabbath offshoot, Heaven and Hell.