Demos and Excursion Demise

Invocator was formed in the summer of 1987 in Esbjerg, from Jacob Hansen's previous band name Black Creed that was started one year prior.^[3] Invocator's first demo proper Genetic Confusion was released in 1988 (the band had released a live demo in 1987). The band played numerous shows in support of the demo, supporting the Danish thrash metal act Artillery, among others. The following demo, Alterations, which sold about 2000 copies, was released in 1989.^[4] Following up on the demo, the band played successful shows with major acts such as Entombed, Edge of Sanity, Psychotic Waltz, Gorefest, and Incubus (now Opprobrium).

Having signed with Swedish/German label Black Mark Production, Invocator released their debut album, Excursion Demise which was recorded at Montezuma Studios in 1991, Stockholm where the likes of Memento Mori and Edge Of Sanity had also recorded albums. The album received a nomination for the Danish Grammy for "best heavy metal album of the year". In support of the album, Invocator played numerous shows with the likes of (Evil Dead, Lȧȧz Rockit, Atheist, Suffocation, Asphyx, Immolation, Bolt Thrower, Benediction, Massacre, Pungent Stench, Atrocity etc.) and toured with renowned US metal act Dark Angel throughout Europe in 1992. The tour was followed by Invocator supporting Sepultura at their Danish "Arise" show in Saga in Copenhagen and then at the Roskilde Festival, playing in front of 5,000 people.

Musically, the album and the early demos fall under the genre rubric of death-thrash metal, containing several extremely fast and aggressive parts, including original lead guitarist' Jakob Schulz' fast Slayer-inspired solos. The average song of that era typically consisting of several different parts and numerous tempo changes, Invocator's early style displays some of the emphasis on technicality and progressivity that would characterize their later releases.

Weave the Apocalypse and Dying to Live

Invocator went through both musical and line-up changes in the time between their first and second albums. The original line-up, which included Jacob Hansen, Jakob Schulz, Jesper M. Jensen and Per M. Jensen, was abandoned as Perle Hansen took up the duty as new lead guitarist, and Per Jakobsen took over the bass duties. The band's new style, which was previewed on a promo tape in 1992, retained the complexity of the debut album, but emphasis on speed had been abandoned an even higher focus on technicality and progressivity taking its place. Not only were Perle Hansen's lead guitar more complex and nuanced than the lead guitar on the debut album, Per M. Jensen's drumming had also become very complex and progressive compared to the high speed pounding of Excursion Demise.

The recording of their second album Weave The Apocalypse began in 1993 with engineer/producer Eric Greif, (uncredited) Death co-producer (Spiritual Healing) and manager, at Elsound Studio in Copenhagen. The release was well received and garnered positive reviews. Weave the Apocalypse is remembered by fans and critics alike as perhaps the strongest Invocator record in terms of songs, musicianship and production.

The band toured with Paradise Lost on their "Icon" Denmark tour, and Invocator recorded two cover songs for a CD, entitled Early Years, featuring their old demo tapes in a remastered version – namely, "The Promise Of Agony" by Dark Angel and "The Eternal War" by Artillery. Early Years marked a label change from Black Mark to Progress/Die Hard Music.

Dying To Live, the band's third album, which musically combines groove metal with the technicality of the predecessor, was recorded and released in 1995, with another line-up change preceding it, as bassist Per Jakobsen being replaced by Carsten Mikkelsen. During a Denmark tour to support the album, the chemistry within the band suffered from different musical directions desired by its different members and the band decided to split the same year. While Per M. Jensen subsequently performed and recorded with Artillery, Konkhra, and Geronimo and would ultimately join The Haunted, Jacob Hansen pursued a successful career as a producer, working with death metallers Pestilence, neo-rockers The Storm, hard rockers Pretty Maids, Volbeat, and progressive metallers Cryoshell and Anubis Gate among others; Hansen eventually joined the latter as their lead vocalist (Anubis Gate also features former Invocator bassist Jesper Jensen, who had also had a stint with Geronimo) and also took up guitar duties in progressive metal band Beyond Twilight.

Through the Flesh to the Soul and the 2010 Headbangers Ball Tour

In the early 2000s, Jacob Hansen started to write new songs together with guitarist Flemming C. Lund, known for his work with Autumn Leaves and The Arcane Order, and a temporary drummer was found in Brian Rasmussen from Behind The Curtain and Mnemic, and in 2002 a demo was released.

Through the Flesh to the Soul was released in 2003 with Hansen on vocals and guitars, Lund on guitars, Mikkelsen, who had rejoined the band, on bass, and Jakob Gundel, also known for his work with Danish melodic death metal act Withering Surface and American progressive metal act Lord Bane, on drums. Through the Flesh to the Soul is more melodic and modern in sound than the preceding albums and also more straightforward with more fast parts. The music is still technical and somewhat complex with some polyrhythmic sections.

After another hiatus, the band went on tour in Denmark with Raunchy and The Burning in 2010 in the Danish leg of the Headbangers Ball Tour with Perle Hansen having rejoined the band. Most of their set consisted of tracks from Weave the Apocalypse and Dying to Live with the title track of Through the Flesh to the Soul and the title track of Excursion Demise being the only tracks from the two other albums. Invocator were joined onstage by guests Flemming G. Lund, who is now in Raunchy, and Jacob Schulz, who had played in now defunct death metal act Maceration along with Jacob Hansen and Dan Swanö, which performed under the pseudonym of Day Disyraah, after Schulz had left Invocator.