“Eagle” is a song that was recorded in 1977 by the Swedish pop group ABBA. It was the first track on the group's fifth album, ABBA: The Album and the longest selection they ever recorded (at 5:51, 1 second longer than "The Day Before You Came" at 5:50). The fourth and last official single from ABBA: The Album, it was released only in a limited number of territories as a double A-side with "Thank You for the Music". “Eagle” was not released as a single in the United Kingdom. It was released in the US, but then withdrawn.

"Eagle" was written and composed by Benny Andersson & Björn Ulvaeus, a kind of a tribute to a band that the main composers of the group admired at the time; The Eagles. The recording, which commenced on 1 June 1977, had the working titles of "High, High" and "The Eagle." Lyricist Ulvaeus was inspired by Richard Bach's novel Jonathan Livingston Seagull when he wrote the lyrics for this song. In later years, music critics have hailed "Eagle" as one of ABBA's more outstanding tracks in terms of lyrics.

"Eagle" was not a major success on the charts. One reason was that the song was already available on The Album; another was the limited release only in countries like Australia, Austria, Belgium (where it did top the charts), France, West Germany, the Netherlands, Switzerland. To make the song more radio-friendly it was heavily edited down from 5:51 to 4:25 by omitting an instrumental break and the 3rd chorus. Australia and France even got an edit from the edit, with the song fading shortly after the 2nd chorus making it last just 3:33, 2:18 shorter than the album version. It was released, then withdrawn, as a single in the United States.

The single was released in May 1978 to fill the gap between the previous single, "Take a Chance on Me" and the next, a completely new track, eventually titled "Summer Night City." The B-side of "Eagle," "Thank You for the Music," was later released as a single outright in a few countries after the group had disbanded, namely in the UK, where "Eagle" had not been released as a single.

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