“I’m Blue, I’m Lonesome” is a 1950 song credited jointly to Bill Monroe and Hank Williams — the only song with a shared Monroe–Williams writer credit. It was first recorded and released by Bill Monroe and his Blue Grass Boys in 1950. The song was written in the late 1940s, when Monroe and Williams shared the bill on some tours, and the canonical account places the song’s origin somewhere on a tour through Texas.
The authorship is more complicated than the joint credit suggests. According to Colin Escott’s biography of Hank Williams, Williams played the song for Monroe on tour, and Monroe somehow ended up with credit on the registration. There are persistent rumors that the song was first registered under the pseudonym “James B. Smith” — possibly a placeholder for both writers — and that royalties initially went solely to Monroe until Acuff-Rose successfully challenged in the 1990s for Williams’s share. Monroe later asserted he did write some of the song; Monroe’s sideman Jimmy Martin has insisted Hank wrote it all. Treat the joint credit as the official register and the actual division of authorial work as unsettled.
Whatever the underlying authorship, the song’s stark high-lonesome character marries Monroe’s bluegrass vocabulary to the country-blues phrasing Williams was developing in the same years. “I’m Blue, I’m Lonesome” remains a regular at jam sessions where pickers want a piece sitting at the boundary between the bluegrass and Hank Williams idioms.