Jerome Kern's 1927 musical Show Boat enjoyed almost immediate success. Ziegfeld himself agreed to stage it in his newly completed theater, and it was so popular he created a second cast for concurrent runs in Philadelphia and New York; the first of four revivals (plus three film versions) took place only three years after the close. Yet Show Boat broke the time's conventional molds for musical theater: it dealt with issues of race in America, two main characters struggle with broken marriages, and even the love songs that appear to flaunt customary standards of sentiment. Oscar Hammerstein's book and lyrics for the show, with Kern's masterful evocation of its sweep through earlier times cast these controversial topics in an instantly popular vehicle. And all of them overlap in the character of Julie. The player who loses her job on the showboat when her mulatto blood and illegal marriage to a white man are revealed, Julie's signature songs are the ironic and simple: "Bill," and the racially charged "Can't Help Lovin' Dat Man."
Kern first gives the audience a taste of "Can't Help Lovin' Dat Man" as Julie tries to comfort the love-struck daughter of the showboat's captain. "Love's a Funny Thing," she says, leaning on her own experience that once love strikes, even finding out that the man's no good will not relieve it. She sings a light ballad about the need to love her one man until she dies, just as a fish must swim and a bird must fly. Yet the song is not just a ballad. The African-American cook Queenie hears her singing it, and asks where she learned the song: Queenie knows it as a black person's melody and a favorite of her husband Joe. Julie, who has been pretending to be fully Caucasian, betrays her true heritage by singing "Can't Help Lovin' Dat Man" in its entirety. Kern's music clearly suggests African-American idioms, with many chromatic "blue notes," swung rhythms, syncopation, and plucked strings emulating a banjo in the accompaniment. Later in the scene, this song breaks racial barriers, as the lily-white Magnolia shuffles her suddenly hot feet to Queenie's rendition. Through the show, this song continues its trajectory alongside the characters, serving as a wedding chorus for Magnolia. Finally, it reappears in different guise as a ragtime in the Chicago entertainment scene, sung by a now-abandoned Magnolia as she tries to forge a new life in a new time.