As with several Led Zeppelin tunes, "'Tangerine' was a song dating back to Jimmy's Yardbirds' days". Page explained "I'd written it after an old emotional upheaval and I just changed a few of the lyrics for the new version". It has been suggested that it may have been influenced by his relationship with Jackie DeShannon, with whom he had been involved with around the time. On April 4, 1968, the Yardbirds recorded "a very similar demo called 'Knowing That I'm Losing You'" during their last recording sessions at the Columbia Studios in New York City. Page composed the music and the Yardbirds' singer Keith Relf contributed the words. The lyrics, that "smack[ed] of the classic flower-child-isms of Keith Relf",  included:
"Knowing That I'm Losing You", along with the other demos recorded during their last sessions, have been seen as half-hearted attempts by the Yardbirds to meet contractual obligations. In 2000, several of these appeared on the Yardbirds' compilation Cumular Limit; however, Page did not consent to the use of "Knowing That I'm Losing You".
Recording and composition
Although written earlier, "Tangerine" fit in with the California-inspired folk-rock numbers that Robert Plant and Jimmy Page were creating for Led Zeppelin III at Bron-Yr-Aur, their rustic retreat in South Snowdonia, Wales. The arrangement and feel have also been likened to that of "'lost love' ballads from 1966–68" that had been "used effectvely on Mickie Most's Donovan sessions in the Yardbirds years when both Jones and Page were still hired hands". Led Zeppelin recorded it at Headley Grange, Headley, East Hampshire, using the Rolling Stones Mobile Studio. The song was engineered and later mixed by Andy Johns at Olympic Studios in London.
The song begins with a "nicely low-key, deliberate-mistake intro", after which Page pauses to set the right tempo with a twelve-string acoustic guitar "strummed A minor–G–D guitar figure". Plant then sings the first verses and bassist John Paul Jones and drummer John Bonham come in at the chorus. Page also adds pedal-steel guitar accompaniment and explains: "I hadn't touched a pedal steel from the first album to the third. It's a pinch really from the things that Chuck Berry did — but nevertheless it fits. It was more out of tune on the first album [for "Your Time Is Gonna Come"] because I hadn't got a kit to put it together". Midsong he also includes "an elegant [electric guitar] solo that seemed to quote Jeff Beck". For the choruses, Plant adds a double-tracked harmony vocal.
Release and influence
"Tangerine" was issued as an album track on Led Zeppelin III on 5 October 1970 in the US and 23 October 1970 in the UK and quickly went to number one on the album charts. It was included on the LP record's second side, which featured more acoustic- and folk-influenced tunes. It has been suggested that "Tangerine" "points the way to the future... the acoustic guitar intro can easily be seen as an early template for 'Stairway to Heaven'". During Led Zeppelin's 1971–72 tours, the song was regularly included in their sets and included on several bootleg albums (see Led Zeppelin bootleg recordings). Several musical artists have performed or recorded it. For cover versions, see List of cover versions of Led Zeppelin songs, "Tangerine".