"When You're Smiling" is a popular song with music by Larry Shay and words by Mark Fisher and Joe Goodwin, published in 1928 by Mills Music. Also known as "When You're Smilin'" and "The Whole World Smiles with You", it was first recorded on 28 May 1928 by Henry Thies and His Hotel Sinton Orchestra, with a vocal refrain by Don Dewey, and released as the single "That's My Mammy" on Victor. Louis Armstrong's 1929 recording made it a major hit of the Jazz Age, and the song became a popular jazz standard from the 1930s. Later notable recordings include those by Billie Holiday with Teddy Wilson (1938), Cliff Bruner's Texas Wanderers with Moon Mullican (1939), which reached the country charts, Frank Sinatra (1950) and Louis Prima (1957). The lyrics and music entered the US public domain in 2024. Adopted by fans in the 1980s, the song is the unofficial anthem of Leicester City Football Club.
