Earlier in this thead Dicho posted "Say, Brothers" from Newman White, "American Negro Folk Songs." White copied it from "The Revivalist," no. 173, p. 92. Does anyone know the date of this publication? I think it would have been a rather late version of the song, but curious about it.
The Library of Congress attributes "Say, Brothers" to William Steffe "about" 1856, and sung around Charleston, SC, but this origin seems to be disputed by others. The use of the tune of the chorus in a popular song (She Had Such Wheedling Ways) published in 1855 (Masato's post in thread 71356) seems to put the origin earlier.
Origin John Brown

Library of Congress discussion: Battle Hymn

The McClellan song sheet posted by Jim Dixon is interesting. John Bull's delivery of supplies to the South in the early years of the war was a strong irritant in the North.