Released on January 23, 1989, the power ballad was written by group member Susanna Hoffs with the established hit songwriting team of Billy Steinberg and Tom Kelly.

Two of the song's three writers, Tom Kelly and Susanna Hoffs, had met via the Bangles' October 30, 1986, concert at the Avalon Hollywood (then the Palace).

[5] Steinberg explained, "Susanna was talking about the Bangles having visited Graceland, and she said there was some type of shrine to Elvis that included some kind of eternal flame.

[2] While the final recording is a power ballad,[7] the demo was deliberately guitar-oriented, despite sounding more suitable for a keyboard, as the Bangles had no keyboardist.

When Hoffs played the demo at a band meeting where members and producer Davitt Sigerson decided what they would record for the upcoming album, it was rejected.

[2] He worked out an arrangement evoking a music box, bringing in keyboardist John Philip Shenale to give the track a chiming effect.

[2] Considered by Billy Steinberg to be a stylistic fusion of the Byrds and the Beatles, especially evoking the latter group's "For No One", "Mother Nature's Son" (the bridge part) and "Here There & Everywhere",[11] "Eternal Flame" elicited different points of comparison from contemporary music critics, among them: "a backhanded tribute to every sappy string-drenched ballad—from Lulu's 'To Sir With Love' to Merrilee Rush's 'Angel of the Morning'—that ever overstayed its welcome on the radio";[12] "[a] fluffy romantic fantasy [that] resembled the Carpenters a lot more than the Beatles";[13] "a cloying ballad that Andrew Lloyd Webber could have written for Sarah Brightman";[14] "[On] 'Eternal Flame' Hoffs does her best inspired reading of Kate Bush".

[17] A retrospective AllMusic critique by Matthew Greenwald assessed "Eternal Flame" as "somewhat removed from the Bangles' sound and vibe...[its] gentle, lilting melody...seems ready-made for an artist such as Anita Baker or Whitney Houston.

[19] The January 1989 release of "Eternal Flame" as the new Bangles' single was heralded in the Chicago Tribune with the song described as an "old-fashioned killer ballad that is just about as far as one could get from the psychedelic sound of the group's recent Top 5 hit 'In Your Room'.

[23] In addition "Eternal Flame" set a record for the song's co-writers: Billy Steinberg and Tom Kelly, as the first songwriting team to score a number-one Hot 100 hit five years in a row.

In 1999, Australian group Human Nature covered "Eternal Flame" and released it as the fourth single from their second album Counting Down.

English girl group Atomic Kitten subsequently recorded the song in 2001 and released it as the lead single from the reissue of their debut studio album, Right Now, on July 23, 2001.

[89] Lars Trillingsgaar, head of music for Danish radio station ANR Hit FM, said that Atomic Kitten's cover of "Eternal Flame" took the original "in a whole new direction", comparing it to another cover of a popular 1980s song that was released in 2001: "Another Day in Paradise" by siblings Brandy and Ray J, originally by Phil Collins.

[90] Atomic Kitten's version was released on July 23, 2001;[90] in Australia, it was issued alongside a re-release of the group's debut single, "Right Now" (1999).

[92][93] The Official Charts Company credits this result to "Bootylicious" having already been released on the parent album, Survivor, whereas the re-release of Right Now did not occur until after "Eternal Flame" had reached number one.

[94][95] In France, Ireland, and Sweden, it reached number two,[94][96] and it became a top-ten hit in Austria, Germany, Hungary, the Netherlands, Portugal, and Switzerland.