Pink Floyd started work on the album after completing their contributions to the soundtrack for the film Zabriskie Point in Rome, which had ended somewhat acrimoniously.

[5] The title track of Atom Heart Mother resulted from a number of instrumental figures the band had composed during these rehearsals, including the chord progression of the main theme, which guitarist David Gilmour had called "Theme from an Imaginary Western",[6][7] and the earliest documented live performance was on 17 January 1970[7] at Hull University.

Consequently, band members Roger Waters and Nick Mason had little choice but to play the bass and drums, respectively, for the entire 23-minute piece in one sitting.

The band had been introduced to Ron Geesin via the Rolling Stones tour manager, Sam Cutler, and were impressed with his composition and tape-editing capabilities, particularly Waters and Mason.

Nobody knew what was wanted, they couldn't read music …"[10] According to him, Gilmour came up with some of the melodic lines, while the pair of them along with keyboardist Richard Wright worked on the middle section with the choir.

[7][14] A refined and improved version (with Geesin's written parts) was played at Bath Festival of Blues and Progressive Music on 27 June.

[13][15] Its name was changed after the band were due to play an "in concert" broadcast for BBC Radio 1 on 16 July 1970, and had needed a title for John Peel to announce it.

[23][25] Side two opens with three five-minute songs: one by each of the band's three resident songwriters; then closes with a sound effects-dominated musical suite primarily conceived by Mason and credited to the whole group.

[29] According to Mason, Gilmour, having had little songwriting experience at that point, was ordered to remain in EMI until he had composed a song suitable for inclusion on the album.

[20] The original album cover, designed by art collective Hipgnosis, shows a Holstein-Friesian cow standing in a pasture with no text nor any other clue as to what might be on the record.

This concept was the group's reaction to the psychedelic space rock imagery associated with Pink Floyd at the time of the album's release; the band wanted to explore all sorts of music without being limited to a particular image or style of performance.

Also, a pink balloon shaped like a cow udder accompanied the album as part of Capitol's marketing strategy campaign to "break" the band in the US.

[32][35][37] Looking back on the artwork, Thorgerson remembered: "I think the cow represents, in terms of the Pink Floyd, part of their humour, which I think is often underestimated or just unwritten about.

"[55] Similarly, in a 1984 interview on BBC Radio 1, Waters said "If somebody said to me now – right – here's a million pounds, go out and play Atom Heart Mother, I'd say you must be fucking joking.

"[12] In a 1970 review, Alec Dubro of Rolling Stone appraised Atom Heart Mother negatively, stating "if Pink Floyd is looking for some new dimensions, they haven't found them here.

[58] Two major performances were at the Bath Festival of Blues and Progressive Music on 27 June and the "Blackhills Garden Party" in Hyde Park, London on 18 July.

[33] According to Mason, the band arrived at one gig in Aachen, Germany, only to discover they had left the sheet music behind, forcing tour manager Tony Howard to go back to London and get it.

[5] A later arrangement without brass or choir, and pared down from 25 minutes to fifteen by omitting the "collage" sections and closing reprise of the main theme, remained in their live repertoire into 1972.

The first live performance of The Dark Side of the Moon suite in Brighton was abandoned partway through; after a break, the band played Atom Heart Mother instead.

[62] On 14 and 15 June 2008, Geesin performed "Atom Heart Mother" with Italian tribute band Mun Floyd over two nights as part of the Chelsea Festival.

[65] In 2013, Geesin produced a book, The Flaming Cow, which documented his experience with working with Pink Floyd, including the making of this album from his point of view.