From the Levy collection:

Title: When Sherman Marched Down to the Sea.
Composer, Lyricist, Arranger: Words by Adjt. Byers, 5th Iowa Cavalry, at Columbia, S.C. Music Composed by E. Mach.
Byers S. C. E. Mach Publication: Philadelphia: Lee & Walker, 722 Chestnut St., 1865.
Form of Composition: strophic
Instrumentation: piano and voice
First Line: Our camp-fires shone bright o'er the mountains, that frowned on the river below
Dedicatee: To R.W. Shields, Esq.

From American Memory:

When Sherman marched down to the sea. 186-
OTHER TITLES
First line: Our camp fires shone bright on the mountain
CREATED/PUBLISHED
Boston, Massachusetts, Oliver Ditson, [186-]

When Sherman marched down to the sea; Marching song of Sherman's army. 1865
Peters, W. C. (William Cumming), 1805-1866
OTHER TITLES
First line: Our camp fires shone bright on the mountain
Chorus: Then sang we the song of our chieftain
CREATED/PUBLISHED
Cincinnati; St. Louis, Ohio; Missouri, A.C. Peters & Bro.; J.L. Peters & Bro., 1865