The Battle Hymn of the Republic lyrics were written by Julia Ward Howe, to the melody of John Brown’s Body, obviously written after John Brown’s hanging in December, 1859. Harriet Beecher Snowe had nothing to do with it.
Thank you for the correction. I was a little uneasy about my facts when I posted that. However, the emotional effects on the issue remain the same.
In an extremely bizarre coincidence, the song was actually originally about an entirely different and totally non-famous John Brown, although when it became popular as a marching song during the early days of the war doubtless few of the singers realized this.
http://www.shrewsburychorale.org/Past/Battle%20Hymn%20of%20the%20Republic.html