Story 
"I Am the Walrus" is a song by the Beatles from their 1967 television film Magical Mystery Tour, and officially released on its soundtrack EP and album. Written by John Lennon and credited to Lennon–McCartney, it was released as the B-side to the single "Hello, Goodbye" and on the Magical Mystery Tour EP and album. In the film, the song underscores a segment in which the band mime to the recording at a deserted airfield. [Wikipedia]
I Am the Walrus is a song by The Beatles, written by Lennon and led on vocal by John Lennon. Three songs spliced together; live BBC King Lear feed in the fade. Within the catalogue, its nonsense thread connects it to Dig a Pony. The orchestral accompaniment showcased George Martin's ear for arrangement, culminating in the almost cathartic declaration 'I am the eggman' layered with experimental sounds (Kozinn 1995, p.169).
The session work falls within the band's Magical Mystery Tour (late 1967) period, recorded 5 Sep 1967 at EMI Studios + Olympic Sound Studios (Barnes) for some MMT/All You Need Is Love work. George Martin produced; Geoff Emerick engineered. For session-by-session detail, see Mark Lewisohn's account on p.122 of The Complete Beatles Recording Sessions (excerpt below). When Lennon presented the song, George Martin was momentarily speechless; the engineer Emerick later recalled watching the band appear mentally detached during recording, noting their lack of engagement with the complex arrangement (Emerick 2006, p.554). Lennon's absurdist composition followed earlier aggressive sarcasm on records and marked a defiant artistic statement amid LSD experimentation and personal turmoil (MacDonald 1994, p.118).
I remember the look of emptiness on all their faces while recording.- Geoff Emerick, Emerick 2006, p.554
What's distinctive
At 4:35 it's among the very longest tracks in the canon (≥97th percentile). One of 101 songs led primarily by John. Recorded approximately 7 of 11 into the Magical Mystery Tour (late 1967) sessions. Carries the unique tag 'spliced' — no other song shares it.
Take count: 25 — takes 1–16 on 5 September 1967 (only five complete), reduced to take 17; the 27 September orchestral session ran takes 18–24 and the Mike Sammes Singers overdub became take 25, but the released master sits on take 17 with every later overdub merged in.
1
John was totally in charge of that. Ringo was turning the dial, and Mr Martin had little to do with it. As with so much to do with the Beatles, what came from the radio at any given time was in the lap of the gods. And let’s face it, anything that came up at that instant would have become part of rock legend.
— Ken Scott2
Frequently asked
Who wrote I Am the Walrus?
“I Am the Walrus” is credited to John Lennon (Lennon–McCartney).
Who sings lead on I Am the Walrus?
The lead vocal on “I Am the Walrus” is by John Lennon.
When was I Am the Walrus recorded?
“I Am the Walrus” was recorded at EMI Studios, Abbey Road, beginning 5 September 1967 (basic track, takes 1–16), with orchestral and Mike Sammes Singers overdubs through 27–28 September and the final mono mix with its live King Lear radio overlay on 29 September 1967.1
How many takes did I Am the Walrus require?
Lewisohn documents takes 1–16 on 5 September 1967, reduced to take 17, then takes 18–24 (27 September orchestra) and take 25 (Mike Sammes Singers); the released master sits on take 17 with the later overdubs merged in.1