Krokus was formed in 1974 as a primarily prog rock act. Chris von Rohr, originally the bassist, switched to lead vocals in the late 1970s and with that formation Krokus was successful in Switzerland, touring throughout the country. After seeing AC/DC in concert in the late 70s, they decided to change their musical direction and adopted a new sound which was heavily influenced by the band. Since von Rohr possessed limited vocal abilities and was not capable of hitting the third octave, the band decided to hire a new lead vocalist. Eventually, Marc Storace, formerly of TEA and Eazy Money, was hired. With the new lineup in place, the band recorded and released a new album entitled Metal Rendez-vous in 1980, bringing much wider international recognition.
The 1981 follow-up album, Hardware, was recorded at the Hammersmith Studios in London and featured such songs as "Easy Rocker" and "Rock City", which are still a part of the band's live repertoire today.
In 1982, with new American management, Krokus recorded One Vice at a Time, which featured the hits, "Long Stick Goes Boom," and the Guess Who cover, "American Woman". Chris von Rohr described the album at the time as "the album AC/DC never made", as the influence of the Australian band is difficult to ignore. The comparisons actually cast doubt on the creativity of the band, as many listeners now began to regard Krokus merely as AC/DC imitators. Nevertheless, Krokus became increasingly popular in Europe and began to receive attention in the United States.
1983's Headhunter was awarded platinum album status in the United States and hit number 25 in the 1983 album charts. The album was Krokus' most successful album to date, both commercially and critically. It boasted the hit power ballad "Screaming in the Night", which saw heavy rotation on MTV and would become one of the band's most recognizable songs. Judas Priest's Rob Halford contributed backing vocals on the song "Ready to Burn".
1984 saw the band move in a more commercial direction with The Blitz, which featured a cover of Sweet's 1973 hit song The Ballroom Blitz. Though a commercial success, the album was panned critically. Capitalizing on the wave of success enjoyed by heavy metal in the mid-1980s, the band then released Change of Address in 1986, which featured a cover of the Alice Cooper standard School's Out. The album was a commercial and critical failure. Krokus then released a live album entitled Alive & Screamin' as the band transitioned from Arista Records to MCA.
In 2005, longtime lead guitarist Fernando von Arb left the band after continuing wrist problems required surgery. Mandy Meyer, who had played with the band in the mid-1980s, replaced von Arb in the lineup. The new formation recorded the studio album Hellraiser in 2006, which went to gold in Switzerland on the first day of sales. It generally received very good reviews. In an interview in 2008, Marc Storace stated that Krokus was becoming more and more "metal".
On 18 November 2007, the line up featuring Chris von Rohr, Fernando von Arb, Freddy Steady and Marc Storace reunited to play a medley ("Tokyo Nights", "Bedside Radio" and "Heatstrokes") during the TV show, Die grössten Schweizer Hits, on Swiss television. This led to their reunion concert on 2 August 2008. Krokus's cover of Sweet's "The Ballroom Blitz" also appeared in the 2007 game Guitar Hero Encore: Rocks the 80s.
It was announced on 20 April 2008, that the classic lineup of Chris von Rohr, Fernando von Arb, Freddy Steady, Mark Kohler and Marc Storace had reunited, and would be releasing a new studio record in 2010 with a supporting world tour. On 2 August 2008, the band performed live in the Stade de Suisse in Bern. Krokus performed the official anthem of the 2009 Ice Hockey World Championships, hosted by Switzerland. The song was entitled "Live for the Action".