Finian's Rainbow, with music by Burton Lane and lyrics by E.Y. Harburg, opened on Broadway in 1947, with Ella Logan and David Wayne in the lead roles. An odd combination of whimsy, romance, and political satire, the plot revolves around Finian McLonergan, who has escaped from Ireland to the town of Rainbow Valley in the mythical state of Missitucky with his daughter Sharon, intent on burying a stolen pot of gold in the shadows of Fort Knox, in the mistaken belief it will grow and multiply. Hot on their heels is Og, a leprechaun intent on recovering his treasure. Complicating matters are the wishes made by those unknowingly in the vicinity of the hidden crock, and a bombastic Senator who makes no effort to conceal his bigotry.

Although a major success, and despite its recognizable score, the musical has not retained its popularity due to its seriously outdated view of the racial situation in the American South.

John Hubley was given an offer to make an animated version of Finian's Rainbow, starring the voice talents of Frank Sinatra and Ella Fitzgerald, but he was blacklisted at the time and was forced to turn it down.

A 1968 film version directed by Francis Ford Coppola starred Fred Astaire as McLonergan, Petula Clark as Sharon, and Tommy Steele as Og. Released at a time when the popularity of movie musicals was on the wane, it was dismissed as inconsequential by most critics, who found Astaire's obviously frail and aged appearance shocking and Steele's manic performance annoying. Highly praised by all was Clark in her American film debut, for which she was nominated a Best Actress Golden Globe Award.

The original soundtrack was finally issued on CD in a limited, numbered edition in 2004. The film was released in DVD format on March 15, 2005.

Well-known songs from the musical include "Look to the Rainbow," "Old Devil Moon," and "How Are Things in Glocca Morra?"