Johnny Mercer wrote I'm an Old Cowhand (From the Rio Grande) in 1936 during a car trip across the United States with his wife, shortly after what appeared to be a failed attempt to establish himself in Hollywood. Mercer was amused by the incongruity of modern cowboys wearing traditional spurs and ten-gallon hats while driving cars and trucks instead of riding horses, an image sharpened by the era's fascination with singing cowboys on film and radio. He reportedly composed the song in fifteen minutes, scribbling the lyrics on the back of an envelope, channeling observational humor and his own frustration with a stalled career into a satirical Western novelty number. Bing Crosby introduced it in the Paramount Pictures film Rhythm on the Range and recorded it with Jimmy Dorsey and his Orchestra for Decca Records in July 1936. The recording became a major hit, reaching number two on the charts, and proved transformative for Mercer's trajectory, prompting him to remain in Hollywood rather than retreating to his hometown of Savannah, Georgia. Crosby became one of Mercer's biggest boosters, subsequently performing and recording numerous Mercer compositions. Sonny Rollins' landmark 1957 album Way Out West, recorded with Ray Brown and Shelly Manne, recast the tune as a swinging hard bop vehicle, stripping away its novelty origins and revealing harmonic possibilities that made it a durable presence in the jazz repertoire. Crosby revisited the song in 1954 for his album Bing: A Musical Autobiography, confirming its enduring place in the American popular songbook.