[1] Emerson wrote and arranged much of ELP's music on albums such as Tarkus (1971) and Brain Salad Surgery (1973), combining his own original compositions with classical or traditional pieces adapted into a rock format.

[5] Although Emerson did not own a record player, he enjoyed listening to music on the radio, particularly Floyd Cramer's 1961 slip note-style "On the Rebound" and the work of Dudley Moore.

[17] While performing in the Worthing and Brighton area, Emerson played in John Brown's Bodies where members of The T-Bones, the backing band of blues singer Gary Farr, offered him a place in their group.

The group's sound was centred on Emerson's Hammond organ showmanship and theatrical abuse of the instrument, and their radical rearrangements of classical music themes as "symphonic rock".

[26][27][28][29] To increase the visual interest of his show, Emerson abused his Hammond L-100 organ by, among other things, hitting it, beating it with a whip, pushing it over, riding it across the stage like a horse, playing with it lying on top of him, and wedging knives into the keyboard.

For the session, Emerson performed with drummer Mitch Mitchell and bassist Chuck Rainey covering, among other tunes, the Eddie Harris instrumental "Freedom Jazz Dance".

[32] Emerson first heard a Moog synthesizer when a record shop owner played him Switched-On Bach (1968) by Wendy Carlos, and thought the instrument looked like "an electronic skiffle".

[33] ELP's record deal provided funds for Emerson to buy his own Moog modular synthesiser from the US, which was a preset model that had fewer leads and punch cards to call up certain patches.

Emerson performed several notable rock arrangements of classical compositions, ranging from J. S. Bach and Modest Mussorgsky to 20th-century composers such as Béla Bartók, Aaron Copland, Leoš Janáček and Alberto Ginastera.

Recorded in the Bahamas with local musicians, it departed from Emerson's usual style in featuring calypso and reggae songs, and was generally not well received,[52] except in Italy where it was a hit.

Changing States also contained an orchestral remake of the ELP song "Abaddon's Bolero" with the London Philharmonic Orchestra, and "The Church", which Emerson composed for the 1989 Michele Soavi horror film of the same name.

Emerson also toured briefly in 1990 with The Best, a supergroup including John Entwistle of The Who, Joe Walsh of the Eagles, Jeff "Skunk" Baxter of Steely Dan and The Doobie Brothers, and Simon Phillips.

[61][62] In the early 1990s, Emerson formed the short-lived group Aliens of Extraordinary Ability with Stuart Smith, Richie Onori, Marvin Sperling and Robbie Wyckoff.

[66][67][68] On 25 July 2010, a one-off Emerson, Lake & Palmer reunion concert closed the High Voltage Festival as the main act in Victoria Park, East London, to commemorate the band's 40th anniversary.

[70][71] Japanese composer Takashi Yoshimatsu worked with Emerson to create an arrangement of ELP's song "Tarkus", which premiered on 14 March 2010, performed by the Tokyo Philharmonic Orchestra.

[78][79][80] In 2000, Emerson was a featured panelist and performer at "The Keyboard Meets Modern Technology", an event honouring Moog presented by the Smithsonian in Washington, D.C., in conjunction with a gallery exhibition celebrating the 300th anniversary of the piano.

[83][84] Emerson opened the Led Zeppelin reunion/Ahmet Ertegun Tribute Concert at the O2 Arena in London on 10 December 2007,[85] along with Chris Squire and Alan White (Yes) and Simon Kirke (Bad Company/Free).

[33] In 1993, Emerson was forced to take a year off from playing after he developed a nerve-related condition affecting his right hand that he likened to "writer's cramp", and that was also reported as a form of arthritis.

During his time off, he ran marathons, customised a Harley-Davidson motorcycle, and wrote film scores and his autobiography, Pictures of an Exhibitionist, which opens and closes with an account of his illness and subsequent arm operation.

[115] In the Nice's 1968 live performance of "Hang on to a Dream" on the German television program Beat-Club (later released on DVD in 1997), Emerson can be seen and heard reaching inside his grand piano at one point and plucking its strings.

Emerson's love of modern music such as Copland and Bartok was evident in his open voicings and use of fifths and fourths, "Fanfare" emulated guitar power chords.

He played the Royal Albert Hall Organ at a show with The Nice on 26 June 1968, where the band controversially burned a painting of an American flag onstage to protest against the Vietnam War.

[137] A review of the DVD release of ELP's 2010 one-off reunion show said that the Korg OASYS "appear[ed] to be Emerson's go-to instrument", although he also used a Hammond C-3 and a Moog with a ribbon controller onstage.

[140] In September 2013 Orchestra Kentucky of Bowling Green gave Emerson their Lifetime Achievement Award in the Arts and Humanities "for his role in bringing classical music to the masses".

[163] Alberto Ginastera, on the other hand, enthusiastically approved Emerson's electronic realisation of the fourth movement of his first piano concerto, which appeared on their album Brain Salad Surgery under the title "Toccata".

During the seventies alongside arrangements of classic tracks and Lake's ballads, a decisive element of EL&P's albums are the compositions featuring music entirely written by Emerson.

His trademark is a very varied range of musical approach: songs with a hard rock impact with a jazz flavour such as "Bitches Crystal", "A Time and a Place", "Living Sin", examples of country or stride piano such as "Jeremy Bender" or "Benny the Bouncer", and adventurous instrumentals difficult to classify in one genre, such as "The Three Fates", "Tank" and "Abaddon's Bolero".

The more structured and complex epic tracks such as "Tarkus", "Trilogy", "The Endless Enigma", "Karn Evil 9", "Pirates", "Memoirs of an Officer and a Gentleman" are all Emerson’s compositions.

A return to the visionary and tumultuous style of progressive music is represented by the album recorded under the name of the Keith Emerson Band, which includes the long suite "The House Of Ocean Born Mary" co-written with Marc Bonilla.

On the UK surreal television comedy series Big Train, Kevin Eldon portrayed Emerson as a Roman slave fighting his enemies with progressive rock.