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Moody Blues -

Progressive rock, or prog rock, began to emerge out of the British psychedelic scene in 1967. This was a period of musical exploration characterized by classical influences and symphonic rock. Early pioneers included the Moody Blues, whose landmark 1967 album 'Days of Future Passed' is cited as one of the first examples of the genre.

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Soft Machine -

British band Soft Machine fused psychedelic rock with jazz elements to become a leading act in what became known as the Canterbury scene, named after the town of Canterbury in Kent. Pictured is the original lineup of Robert Wyatt, Daevid Allen, Kevin Ayers, and Mike Ratledge.

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The Nice -

The Nice, meanwhile, also blended rock, jazz, and classical music. The quartet of Lee Jackson, Keith Emerson, David O'List, and Brian Davison enjoyed their first commercial success with an instrumental rearrangement of Leonard Bernstein's 'America,' a song from the 1957 musical 'West Side Story.' Keith Emerson would later become a founding member of Emerson, Lake & Palmer.

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Pink Floyd -

Pink Floyd co-founder and front man Syd Barrett had developed a distinctly whimsical style of psychedelia before his departure and replacement by David Gilmore steered the band towards a more progressive rock direction. 'Ummagumma' (1969) essentially marks Floyd's progressive era.

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The Beatles -

The Beatles, whose groundbreaking 1967 album 'Sgt. Pepper's Lonely Hearts Club Band' provided an early prog rock template, signed off with 'Abbey Road' two years later.

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King Crimson -

King Crimson, founded in 1968 by Robert Fripp, Michael Giles, Greg Lake (later of ELP), Ian McDonald, and lyricist Peter Sinfield combined multilayered elements of classical, jazz, and folk music that provided the foundations for 'In the Court of the Crimson King.' Released in 1969, it's another seminal album in the prog rock canon, and certainly one of the most influential.

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Deep Purple -

Originally formed as a psychedelic rock and progressive rock band, Deep Purple appeared to solidify their prog rock credentials with their groundbreaking 1969 gig at the Royal Albert Hall in London, which was recorded and released as the live album 'Concerto for Group and Orchestra.' The following year, however, they shifted to a heavier sound with their 1970 album 'Deep Purple in Rock' to become one of the pioneers of heavy metal.

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Genesis -

The 1970s ushered in an astonishingly fertile and creative prog rock timeline, and produced some of the most iconic and memorable progressive rock acts of all time. Among them was Genesis. The band's 1970 album 'Trespass' introduced audiences to a more folk-rock flavored sound and featured original guitarist Anthony Phillips and drummer John Mayhew. The classic lineup of Tony Banks, Phil Collins, Mike Rutherford, Steve Hackett, and Peter Gabriel (pictured) was finalized in August 1970.

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Emerson, Lake & Palmer -

One of prog rock's first supergroups was Emerson, Lake & Palmer. The trio of Keith Emerson, Greg Lake, and Carl Palmer was one of the most popular and commercially successful progressive rock groups of the 1970s. Known for their complex adaptations of classical music mixed with jazz and symphonic rock elements, ELP helped define the genre with albums such as 'Pictures at an Exhibition' (1971) and 'Brain Salad Surgery' (1973).

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Yes -

Another band that achieved global fame in the 1970s was Yes. Founded in 1968, the lineup of Peter Banks, Tony Kaye, Chris Squire, Bill Bruford, Jon Anderson were responsible for 1970's 'Time and a Word' before 'The Yes Album' of 1971, with Steve Howe replacing Banks, garnered critical acclaim and launched the band as a formidable prog rock act.

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Gentle Giant -

While Gentle Giant, comprising Gary Green, Kerry Minnear, Derek Shulman, Ray Shulman, Phil Shulman, and Malcolm Mortimore, never achieved commercial success, the complexity and sophistication of their music influenced a generation of musicians, the act eventually achieving cult status among prog rock diehards.

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Van der Graaf Generator -

The odd-sounding Van der Graaf Generator were formed in Manchester in the late 1960s by singer-songwriters Peter Hammill and Chris Judge Smith. Lyrically and musically darker than their contemporaries, the band achieved more success across Europe than in Great Britain, especially with 'Pawn Hearts,' their fourth album released in 1971. Pictured is the later lineup up of Hugh Banton, Peter Hammill, Dave Jackson, and Guy Evans.

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Jethro Tull -

Few epitomize the prog rock musician more than Jethro Tull's Ian Anderson. The multi-instrumentalist has fronted the band since its formation in 1967. 'Stand Up' (1969) provided Jethro Tull with their breakthrough album, Anderson's signature flute underpinning the band's eclectic folk rock soundtrack.

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Curved Air -

'Air Conditioning,' released in 1970, marked Curved Air's debut album. Two of the band's musicians, Darryl Way and Francis Monkman, were classically trained. Lead vocalist Sonja Kristina, who starred in the original London production of the seminal 1960's musical 'Hair,' still fronts the band.

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Gong -

Gong was formed in Paris in 1967 by Australian musician Daevid Allen (of Soft Machine fame) and English vocalist Gilli Smyth. The band somewhat broke the traditional prog rock sound by introducing elements of space rock into their repertoire, using synthesizers and distorted and reverberation-laden guitars over dreamy lyrics that explored themes of outer space and science fiction.

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Camel -

Inspiration for Camel's 1975 breakthrough album 'The Snow Goose' was drawn from American author Paul Gallico's eponymous 1940 novella. Seen here rehearsing in the mid-70s are keyboard player Peter Bardens, drummer Andy Ward, bassist Doug Ferguson, and guitarist Andrew Latimer.

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Greenslade -

Greenslade, named for keyboard player Dave Greenslade, made an impression in 1973 with 'Bedside Manners Are Extra.' Augmented by Dave Lawson, Tony Reeves, and Andrew McCulloch, the band from Guilford in Surrey had never played the tracks live before setting them down on tape in the studio, but cut each song as if performing to a live audience with minimal overdubs and no editing together of different takes.

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Barclay James Harvest -

A four-piece band with a three-piece name, Barclay James Harvest originally comprised Les Holroyd, John Lees, Mel Pritchard, and Stuart Wolstenholme. In typical prog rock style, their eponymous 1970 album featured backing by an orchestra. The band subsequently toured with a full complement of strings and horns.

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Utopia -

Prog rock took longer to emerge in the United States, although bands like The Beach Boys and The Byrds had cemented its foundations in the mid-1960s by fusing elements of cultivated music with the vernacular traditions of rock. In 1973, American multi-instrumentalist Todd Rundgren expanded his musical style by moving from a pop-oriented sound towards progressive rock with the release of 'Todd Rundgren's Utopia.' Other notable US bands promoting the genre included Happy the Man, Ethos, and Starcastle.

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Magma -

But it was in Europe that prog rock proved more forward-looking. In France, for example, Magma developed their own style of progressive rock called "Zeuhl"—an extraordinary collective of contemporary classical music, romanticism, minimalism, modernism, jazz, heavy metal, and jazz fusion.

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Focus -

Dutch outfit Focus—originally Thijs van Leer, Martin Dresden, Hans Cleuver, and Jan Akkerman—enjoyed an international hit with 'Hocus Pocus,' taken from the band's second album, 'Moving Waves' (1971).

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Premiata Forneria Marconi -

Italy, perhaps surprisingly, produced a string of notable prog rock bands in the 1970s, groups like Premiata Forneria Marconi, who matched their British counterparts in creativity and musicianship.

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Aphrodite's Child -

For much of their career, Greek outfit Aphrodite's Child were happy releasing pop records into the mainstream. But in 1972, they turned the tide with '666,' an ambitious and pivotal prog rock concept album that in fact became the band's swan song. Two of its members would go on to achieve worldwide fame—vocalist Demis Roussos and keyboard maestro Vangelis Papathanassiou.

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Virgin Records -

The advent of progressive rock also witnessed the establishment of several British record companies, notably Virgin Records–founded by a young entrepreneur named Richard Branson.

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Vertigo Records -

Vertigo Records, founded in 1969, also played an important role in the development of progressive rock, signing acts like Colosseum, one of the first bands to fuse jazz, rock, and blues, and whose keyboard player, Dave Greenslade, would later form the aforementioned Greenslade.

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Charisma Records -

Among the most successful acts signed by Charisma Records, founded in 1969 by Tony Stratton-Smith, was Genesis. Stratton-Smith knew his stuff, having previously acted as manager for prog rock bands such as The Nice and Van der Graaf Generator.

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Chrysalis Records -

Chrysalis Records recorded acts included Jethro Tull and Procol Harum, whose 'Whiter Shade of Pale,' released in 1967, remains one of the most successful singles of the era, having sold over 10 million copies worldwide.

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Advances in instrument technology -

With prog rock came the arrival of new technical gear and electronic musical instruments. These early synthesizers, such as that developed by American inventor Robert Moog, played an essential role in the development of progressive rock.

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The sound of synth -

In fact, virtuoso keyboard players such as Rick Wakeman, a later member of prog rock band Yes, were able to forge out successful solo careers by combining synthesizers with the piano.

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Striking a new chord -

Similarly, prog rock made solo stars out of string instrumentalists, for example former Genesis guitarist Steve Hackett who took advantage of technical advances in his use of pedals, volume, and other devices added to embellish sound textures.

Sources: (Rock & Roll Hall of Fame) (Prog Archives) (Louder Sound)

See also: The world's greatest rock guitarists

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