1984: Mayhem is formed. Euronymous on guitar, Necrobutcher on bass, Manheim on drums. Their band name is taken from the Venom song Mayhem with Mercy.1986: First gig on April 20th. The first demo, Pure Fucking Armageddon is released. Messiah later joins as session vocalist. At some point Messiah leaves. Later, Maniac joins as permanent vocalist. Split tape with Vomit is released.1987: Deathrehearsal is released. Second demo, Deathcrush, is released. Messiah does vocals for two tracks, Maniac does the rest. Manheim and Maniac leave Mayhem. Torben (drums) and Kittil (vocals) from the band Vomit, join Mayhem, but both leave shortly thereafter.1988: Dead joins the band as vocalist and Hellhammer joins as drummer about 6 months later.1990: Freezing Moon and Carnage are recorded for the CBR Compilation.1991: Dead kills himself in April. Necrobutcher leaves the band. Occultus joins Mayhem as bassist/vocalist to take their places, but leaves shortly after joining. Euronymous, with the help of Occultus and Geir Bratelli, opens up Helvete in Oslo. The name for the store comes from Metalion at Slayer Mag.1993: Recording for De Mysteriis Dom Sathanas is completed. Attila Csihar handles the vocals, Count Grishnackh handles bass, Blackthorn is second guitarist. Live In Leipzig is released and dedicated to Dead. Euronymous is murdered by Count Grishnackh. Mayhem ceases to exist.1994: De Mysteriis Dom Sathanas is finally released and dedicated to Euronymous. Mayhem is reformed by Hellhammer, original vocalist Maniac, original bassist Necrobutcher, and new guitarist Blasphemer (from fellow Norwegian band Aura Noir). Out From The Dark is released, as is the Ancient Skin/Necrolust single.1996: Freezing Moon Picture LP is released.1997: Wolfs Lair Abyss mLP/mCD is released. Alexander Nordgaren joins as live rhythm guitarist, plays during the Mayhem Invades England tour.1998: Nordgaren stays on during rehearsals, later leaves the band when he moves to England.1999: Mediolanum Capta Est is released. Split 7" with Zyklon-B is released.2000: Grand Declaration Of War is released.2001: European Legions: Live In Marseille is released on VHS/DVD, also as limited edition CD. European Legions and U.S. Legions are released.2002: Split 7inch w/ Meads Of Asphodel released, later released on CD with bonus tracks. The Stuidio Experience box set is released.2004: Chimera is released. Maniac leaves in mid November. Attila rejoins Mayhem.2007: Ordo Ad Chao is released.2008: Blasphemer leaves Mayhem. Morfeus (Dimension F3h, ex-Limbonic Art) joins the band as live guitarist for South American tour.2009: Silmaeth (ex-Vorkreist) is added to the line up as second live guitarist. The band will now evolve with 2 guitarists.