For individual tune histories, see Andrew Kuntz's  The Fiddler's Companion

See also, if you haven't already:

Band Music from the Civil War Era
An American Ballroom Companion: Dance Instruction Manuals ca. 1490-1920
"We'll Sing to Abe Our Song!": Sheet Music about Lincoln, Emancipation, and the Civil War
Historic American Sheet Music 1850-1920

Though representing an earlier repertoire, you may find this helpful:  Fiddle Tunes from the American Revolution