According to James J. Fuld (The Book of World-Famous Music, 5th ed., 2000, p. 132):

The written record begins in 1857-1858. On Dec. 19, 1857, there was a copyright entry by Charles Dunbar, Camp Meeting Harp and Revival Chorister. Though no copy of a book with this title has been found, a book entitled The Union Harp and Revival Chorister, with the collection selected and arranged by Charles Dunbar, and a statement that it was published in Cincinnati in 1858, has been found; and it contains at page 264 the music and words of "My Brother Will You Meet Me." The opening words are "Say my brother will you meet me." The music of the Glory Hallelujah chorus is present, but not the words. No copyright entry was made for this book in 1858, although Dunbar copyrighted several other books during that year and copyrighted the second edition of The Union Harp and Revival Chorister on April 30, 1859.