Therion is a Swedish symphonic metal band. Its name originates from Greek, where therion (θηρίον) means beast; the name refers to the beast of the Christian Book of Revelation, however the band's name itself originates from the Celtic Frost album To Mega Therion. Therion was founded by Christofer Johnsson in 1987. Beginning as a death metal band, they later turned to combining orchestral elements with their metal music employing heavy use of choirs and classical musicians.
Therion's music takes its themes from different mythologies and is based on concepts ranging from occultism, magic and ancient traditions and writings. The majority of their lyrics are written by Thomas Karlsson, head and founder of the magical order Dragon Rouge of which Johnsson is a member. The band has seen many changes in line-up and style throughout its history.
Therion were formed originally under the name Blitzkrieg in Upplands Väsby, Sweden. The founder, Christofer Johnsson was originally the bassist and vocalist, he had only played the bass for a few months prior to forming the band. Joining him in this new band were Peter Hansson on guitar and Oskar Forss on drums. Johnsson and Hansson had met in several musical groups, while Forss was an old school friend of Johnsson's.
Blitzkrieg were mainly influenced by the bands Metallica and Slayer, but their sound was similar to the bands Venom and Motörhead. The band however never recorded any proper demos, and only did two concerts together before deciding to split up in 1988, only a few recordings surviving till this day. Johnsson however did not give up the idea and switched to guitar and began to be influenced by the Swiss band Celtic Frost. The band was reformed under the new name Megatherion with the original line-up returning, the name was shortened to Therion almost instantly. Johnsson decided to concentrate fully on vocals and guitar, so Erik Gustafsson from the death metal band Dismember joined as a bassist.