"When the Saints Go Marching In", often referred to as simply "The Saints", is a traditional black spiritual.[1][2] It originated as a Christian hymn, but is often played by jazz bands. One of the most famous jazz recordings of "The Saints" was made on May 13, 1938, by Louis Armstrong and his orchestra.[3]
The song is sometimes confused with a similarly titled 1896 composition: "When the Saints Are Marching In", by Katharine Purvis (lyrics) and James Milton Black (music).[4]