Formation and first releases (1981–1985)
Mercyful Fate was originally formed in Copenhagen, Denmark, in 1981, following the dissolution of the band Brats. Brats had been a punk/metal band, featuring future Mercyful Fate members, vocalist King Diamond, and guitarists Hank Shermann and Michael Denner. After two studio albums and several line-up changes (including the addition of Diamond and the departure of Denner), Diamond and Shermann began writing new material that was much heavier than any of Brats' previous work. The band's record label CBS was not pleased with the material, and demanded they stop singing in English and become more commercial. As a result, Diamond and Shermann quit the group and went on to form Mercyful Fate. Former Rock Nalle bassist Ole Beich (later of L.A. Guns and Guns N' Roses) briefly joined the band around this time. After several line-up changes and semi-professional demo tapes, Mercyful Fate released their self-titled EP in 1982. This line-up, consisting of King Diamond, Hank Shermann, bassist Timi Hansen, drummer Kim Ruzz and guitarist Michael Denner, would go on to record the group's first two studio albums.
In July, 1983, Mercyful Fate recorded their debut album at Easy Sound Recording, in Copenhagen, Denmark. Entitled Melissa, the album was produced by Henrik Lund and released on October 30, 1983 on Roadrunner Records. The character of Melissa, a witch who was burned at the stake, appears for the first time on the eponymous debut album and intermittently throughout the band's later work. After a number of concerts around Denmark, Mercyful Fate entered the studio in May 1984 to record their second studio album Don't Break the Oath, which was released on September 7, 1984. During the album's supporting tour, the band played the US for two months and made festival appearances in Germany. Despite winning a cult following around the world, Mercyful Fate broke up in April, 1985, due to musical differences. Guitarist Hank Shermann wanted the band to move to a more commercial sound; King Diamond refused and announced his departure from Mercyful Fate, which led to the band breaking-up.
After disbanding (1985–1992)
After Mercyful Fate broke up in 1985, King Diamond, along with Michael Denner and Timi Hansen, formed the eponymous King Diamond band. Both Denner and Hansen stayed with the group until 1987's Abigail, after which both left King Diamond. They were replaced by Mike Moon and Hal Patino, respectively, and King Diamond continued releasing albums even after Mercyful Fate had reformed. After leaving King Diamond, Michael Denner opened up a recordshop in Copenhagen, until 1988, when he formed the band Lavina (which would later become Zoser Mez), along with former bandmate Hank Shermann. Hank Shermann had formed the hard rock band Fate in 1985, after having left Mercyful Fate. With Fate, Shermann released two albums: 1985's Fate and 1986's A Matter of Attitude. After leaving the band, Shermann joined-up with Michael Denner to form Lavina.
During the time Mercyful Fate were disbanded, Roadrunner Records released three Mercyful Fate compilation albums. The Beginning was released on June 24, 1987, and featured material from the band's 1982 self-titled EP, as well as rare live and studio recordings. On May 12, 1992, Return of the Vampire was released, which was another compilation of rare studio recordings. On October 6, 1992, Roadrunner released A Dangerous Meeting; a split-release featuring material from both Mercyful Fate and King Diamond.
In 1993, King Diamond, Hank Shermann, Michael Denner and Timi Hansen reunited to reform Mercyful Fate (drummer Kim Ruzz was replaced by Morten Nielsen). The result was the album In the Shadows, which was released on June 22, 1993, through Metal Blade Records. The album also featured a guest appearance by Metallica drummer Lars Ulrich (a fellow Dane), on the track "Return of the Vampire". For the album's supporting tour, Morten Nielsen was replaced by King Diamond drummer Snowy Shaw, due to a knee injury Nielsen had sustained. Bassist Timi Hansen was also replaced by Sharlee D'Angelo, as Hansen did not want to take part in touring. On June 27, 1994, the band released The Bell Witch, an EP of live tracks, as well as studio recordings from In the Shadows.
On September 25, 1994, Mercyful Fate released the album Time, which was recorded and mixed at the Dallas Sound Lab during May–August 1994. After the album's release drummer Snowy Shaw was replaced by Bjarne T. Holm for the Time Tour. Holm had originally been asked to join Mercyful Fate back in 1981, but had declined due to prior commitments. The band spent January through February 1996 recording and mixing the album Into the Unknown, which was released on August 20, 1996. After the album's release, guitarist Michael Denner left the band and was replaced by Mike Wead. In October 1997, Mercyful Fate began recording the album Dead Again at the Nomad Recording Studio in Carrollton, Texas. Dead Again was released on June 9, 1998. In February 1999, Mercyful Fate began recording the album 9, which was released on May 15, 1999.
Hiatus and sporadic reunions (1999–present)
After the supporting tour for 9, Mercyful Fate was put on hiatus. King Diamond focused on his eponymous band, along with guitarist Mike Wead, who joined the group during the European House of God tour. Hank Shermann and Bjarne T. Holm reunited with Michael Denner to form Force of Evil, while Sharlee D'Angelo joined the band Arch Enemy. When asked about the current state of the band in 2008, Diamond stated that Mercyful Fate is currently "hibernating", and that "it's definitely not finished, at least in my book." In August 2008, King Diamond was asked by Metallica drummer Lars Ulrich if Mercyful Fate would be willing to participate in Activision's Guitar Hero: Metallica video game. Ulrich requested the original masters for two of the band's songs, so they could be used in the game. Unable to locate them, Diamond suggested to Activision the band re-record the songs, and as a result, King Diamond, Hank Shermann, Michael Denner, Timi Hansen and Bjarne T. Holm reunited to re-record the songs "Evil" and "Curse of the Pharaohs". King Diamond was also made into a playable character in the game.
On December 7, 2011, King Diamond, Hank Shermann, Michael Denner and Timi Hansen reunited onstage at Metallica's 30th Anniversary concert, at the Fillmore in San Francisco, California, where they, alongside Metallica, performed Metallica's "Mercyful Fate" medley from Garage Inc.
On August 1, 2019, it was announced that Mercyful Fate would be performing an unspecified number of concerts throughout Europe in the summer of 2020. The band's line-up will consist of King Diamond on vocals, Hank Shermann on guitar, Bjarne T. Holm on drums, Mike Wead on guitar and Joey Vera on bass, who is filling in for Timi Hansen as he battles cancer. Aside from previously released material, the band will also be performing new songs over the course of the summer.