"When the Saints Go Marching In." often referred to as
"The Saints," is a United States gospel hymn that has
taken on certain aspects of folk music. The song is a
slight modification (in 1927) of the similarly titled
song "When the Saints are Marching In" from 1896 by
Katharine Purvis (lyrics) and James Milton Black
(music). Though it originated as a spiritual, today
people are more likely to hear it played by a jazz band
(Wikipédia).
SHEET MUSIC