With the intent to create dark music inspired by the likes of Celtic Frost and Christian Death, a demo was recorded in 1989. Although only 150 copies of this cassette were made, it impressed other bands in the underground metal scene and became a cult item, regardless of this fact, the band broke up for a short period of time in 1990.
In 1991 Obscure Plasma Records picked two tracks from the band's demo and released a split single with Rotting Christ - this release garnered particular acclaim in Norway where the band was set to sign with Euronymous' Deathlike Silence Productions, unfortunately Euronymous' murder by Burzum member Varg Vikernes made any record deal impossible for the band.
In 1994 Mammarella recruited a new lineup and in 1995 they signed to English Label Misanthropy Records and released the critically acclaimed In Absentia Christi, after which the band ceased activity once more.
In 2002, Roberto Mammarella resurfaced with a completely new line-up to record the album Ad Nauseam. In 2004 Monumentum briefly resumed activity to contribute to the Tribute To Dead Can Dance: The Lotus Eaters CD (covering "Windfall"). As of 2004, the band has disbanded permanently.