After the group formed in the spring of 1970, they entered rehearsals and prepared material for an album which became a mix of original songs and rock arrangements of classical music.

[2][3] Lake's song "Lucky Man" was released as a single in 1970 and helped the group achieve radio airplay; it peaked at No.

After a warm-up gig in Plymouth, the band performed songs from the album at their next, a spot at the 1970 Isle of Wight Festival which propelled them to widespread fame.

In 2012, Steven Wilson prepared a special edition that features a new stereo and 5.1 surround sound mixes, plus bonus material.

"The Barbarian" is an arrangement of Béla Bartók's 1911 piano piece Allegro Barbaro, but original early pressings of the album credit the track to the group.

"Knife-Edge" is based on the first movement of Leoš Janáček's orchestral piece Sinfonietta (1926),[5] with an instrumental middle section that includes an extended quotation from the Allemande of Johann Sebastian Bach's first French Suite No.

The "Clotho" movement was recorded at the Royal Festival Hall in London, with Emerson playing the venue's pipe organ.

"Lachesis" is a short piano piece that features baroque and jazz influences, ending in grand, sweeping arpeggios.

[14] Reviewing in Christgau's Record Guide: Rock Albums of the Seventies (1981), Robert Christgau said: "This opens with 'The Barbarian,' a keyboard showpiece (not to slight all the flailing and booming underneath) replete with the shifts of tempo, time, key, and dynamics beloved of these bozos.

"[13] In a retrospective review, Bruce Eder at AllMusic claimed it "showcased the group at its least pretentious and most musicianly"[12] while The Daily Vault hailed it as a "dizzying mix of keyboard solos, incredible bass work, excellent vocals and powerful drums".

The first two sections of "The Three Fates" ("Clotho" and "Lachesis") and "Tank" were omitted, for multitrack tapes for these pieces were unavailable; meanwhile, unreleased material was added.