There are several fragments of "Ain't Gonna Rain No More" from 1919 or so in collections, and "the words of a refrain "Ain't Goin' to Rain No Mo'" in JAFL, Sept. 1911, p. 277 under the title "I Ain't Bother Yet" (Fuld).

Fuld notes that the last four bars of "Satan's Camp Afire" in Allen's "Slave Songs of the United States" (1867) have a similar melody. Anecdotally, Sandburg reports that the song is "at least as old as the 1870's." Fuld, J. J., 1966, "The Book of World-Famous Music," p. 307. (Dover, 1985, 3rd. ed.)

"Satan's Camp Afire" is no. 36 in Allen. http://docsouth.unc.edu/church/allen/allen.html

LYR. ADD: SATAN'S CAMP A-FIRE
(Coll. Allen, 1867)

Fier, my Saviour, fier,
Satan's camp a-fire;
Fier, believer, Fier,
Satan's Camp a-fire.

Fragment, with score, no. 36. William Francis Allen, in Ware and Garrison.
The score in Irving Schlein, 1965, "Slave Songs of the United States," p. 64, is not the same.

See Traditional Ballad Index for discussion and examples of "It Ain't Gonna Rain No More," including Brown, 1919.
http://www.csufresno.edu/folklore/BalladSearch.html
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