Formed in 1993 by guitarist Roine Stolt as a touring band to support his solo album The Flower King, the band stayed together after the tour and has gone on to become one of the most prolific studio recording units in rock music of their era.
The original line-up for Stolt's solo album consisted of Stolt (vocals, electric guitar, bass, keyboards), Jamie Salazar (drums), and Hasse Fröberg (vocals). When the full band was formed, they added Michael Stolt (bass) and Tomas Bodin (keyboards). Michael Stolt and Salazar have both left the band since its formation, replaced by Jonas Reingold (bass) and Zoltan Csörsz (drums). Other contributors have included Hasse Bruniusson (percussion) and Ulf Wallander (saxophone).
Roine Stolt has written the vast majority of the material the band has recorded, with Bodin contributed most of the rest. The music is perhaps best described as "symphonic", bearing a strong resemblance to that of Yes.
Their 1999 album Flower Power contains what is thought to be the longest progressive rock track ever recorded, the eighteen section, sixty-four minute long "The Garden of Dreams".