First recorded and performed (in Breakfast at Tiffany’s) by Audrey Hepburn (1961, released 1993).
Hit versions by co-writer Henry Mancini (US#11/MOR #3/UK #44 Oct 1961), Jerry Butler (US #11/MOR #3/R&B #14 Oct 1961), Danny Williams (UK #1 Nov 1961).
Also recorded by Andy Williams (1961).
From the wiki: “‘Moon River’ was written by Henry Mancini and Johnny Mercer, and was used as Audrey Hepburn’s theme song in the 1961 movie Breakfast at Tiffany’s. Hepburn sings the song in the movie, but the version used on the soundtrack was an instrumental by Henry Mancini and his orchestra. Mancini’s instrumental version was released as a single, the first to chart in the US and UK. Hepburn’s version, even though recorded first, was not released until after her death in 1993. It then appeared on the album Music From The Films of Audrey Hepburn.
“Although the instrumental version is played over the film’s opening titles, the lyrics are first heard in a scene where Paul ‘Fred’ Varjak (George Peppard) discovers Holly Golightly (Hepburn) singing them, accompanied by her guitar, on the fire escape outside their apartments. There was an eruption of much behind-the-scenes consternation when a Paramount Pictures executive, Martin Rackin, suggested deleting the song from the film immediately after a very successful San Francisco preview. Hepburn’s reaction was described by Mancini and others in degrees varying from her saying ‘over my dead body’ to her using somewhat more colorful language to make the same point.