The story of Faethom began in Cochabamba - Bolivia, deep in the heart of South America. Co-founders David Diacrono and Mariela Muerte joined their dark talents to mix that which they most love: Story Telling and Heavy Metal. Terror tales written by Mariela eventually became songs. Mariela and David relocated to Fort Lauderdale, Florida where they shaped up the sound of what would later become Faethom in the next few years. Mariela and David recorded a 2 song Demo in 2008 and enlisted the talents of Argentinean bassist Federico Vidal and Californian drummer Thomas Wittig for the live experience. This lineup played the first live show on November 14th of 2009 at which they released a 5 song EP titled “Lullaby for Heathen Spawn”.

Thomas parted ways with Faethom in 2010 and the band reunited with Colombian drummer Hermes Reyes, who had temporarily started practicing with the band prior to its first show. Also, Chilean guitarist Fabian Lopez was added to the rhythm section in 2011. Faethom released their first full length concept album titled “In the Name of the Father, the Son, and the Unholy”, played numerous shows across Florida, as well as the first show outside of the state in Alabama that same year.

By the end of 2012 and beginning of 2013 the band parted ways with Fabian and bassist Federico. In October of 2013, the remaining members released "Mark of the Devil", an EP containing 3 new songs which would later become part of the second concept album. Mariela recorded Vocals and Keys, David recorded Guitars and Bass, and Hermes recorded Drums. The same year bassist Matt Winters and guitarist Leona Hayward were added to the lineup and the band started playing shows as a five piece once again. In 2014 Leona Hayward switched to bass after Matt Winters' departure and this lineup played numerous shows including the first show outside of mainland U.S. in Guaynavo Puerto Rico. This 4 piece lineup went on to record the next full length concept album named "Fury of the Scorned Witch”.

Saddly, Leona ended up moving to Seattle, WA by the end of 2015 during the mixing stage of the album, which would not allow her to continue in the band. Bassist Marcel Salas joined the band to fill the gap and became a permanent member of the band in early 2016. Fury of the Scorned Witch was released on July 1st of 2016 and Brian Wilson (Hellwitch, Yngwie Malmsteen) filled-in on drums in order to embark on the first U.S. tour in support of the album with SOLSTICE (U.S.A) as tour headliners.

In 2018 Mariela and David focused their creative efforts on writing all the new material for Faethom's third concept album. The same year saw the departure of drummer Hermes as well as bassist Marcel, and in early of 2019 the band welcomed Ibrahim Hernandez on bass (Synepticide, Made of Metal) originally from Venezuela, and drummer Roy A. Jurado Caceres (Sapraemia, Ancestor, Made of Metal) originally from Peru. The band began working on bass & drum arrangements gearing up towards going into the studio to record the third full length album later in 2019. Some of the new songs were performed live throughout 2019 including during a small tour in support of Vicious Rumors' 40th Anniversary in June which also marked FAETHOM's 10th Anniversary adding new energy and momentum to the album's creation. After playing many live shows through 2019, both Ibrahim and Roy exited the band as they decided to move to Chicago and Massachusetts respectively, so once again the band began searching for new members.

By the beginning of 2020, the band re-enlisted Brian Wilson on drums only this time as a permanent member and soon after enlisted Bill Bryant (SAQ) on guitar to continue working on arranging the new songs for proper recording. The pandemic temporarily paralyzed the band due to no longer having an available rehearsal studio, however, the band enlisted Evie Austin (Inscribed) in early 2022 to once again have a full line up for live shows and began recording the new album. Brian's drums and David's guitars were recorded at Derek Roddy's (Divine Empire, Hate Eternal, Malevolent Creation) studio and Evie's bass as well as Mariela's keyboards and vocals were recorded at David's home studio. The album was then mixed and mastered by Jörg Uken at Soundlodge Studios in Germany. The new band lineup performed live again on February of 2023, except for Billy Bryant, who was too ill to perform and unfortunately lost his battle with Cancer in May of 2023.

Chaosmorphogoria, the new concept album, finally saw the light on Friday, October 13th of 2023 and the whole album plus a few classics were performed twice, first in Pompano Beach, FL on October 26th and again in Tampa, FL on October 28th as the band headlined the BLACK MASS III festival.

Through the years Faethom played shows along the likes of Morbid Angel, Raven, Venom Inc, Taake, 1349, 3 Inches of Blood, Goatwhore, Arkona, Agalloch, Anvil, Terrorizer, Nocturnus AD, Toxic Holocaust, Deceased , Vicious Rumors, Imperial Triumphant, and Satan while continuing to spread the music to new audiences.