The famous Union marching song "John Brown's Body" was written at the fort using a tune from an old Methodist camp song, and was performed at a flag-raising there on 12 May 1861. The song was carried to the Army of the Potomac by the men of the "Webster Regiment" (12th Massachusetts Infantry), who had mustered in at Fort Warren. Julia Ward Howe heard this song while visiting Washington, DC. At the suggestion of her minister, Howe was encouraged to write new words. "The Battle Hymn of the Republic", which was initially published as a poem, was later matched with the melody of the "John Brown" song and became one of the best remembered songs of the Civil War era.