"Just before the Battle, Mother" was a popular song during the Civil War, particularly among troops in the Union Army. It was written and published by Chicago-based George F. Root (1820-1895). Root also wrote some of the best known songs of the Civil War era including "Tramp! Tramp! Tramp!", "The Vacant Chair" and "The Battle Cry of Freedom". It enjoyed great success overseas as well. The British, in fact, believed that the song was about the Crimean War and had been written by an Englishman.
The "traitors" mentioned in the second verse of the song were not Confederates but Northern Copperheads, who wished to see the War end through a negotiated peace and recognition of a new Confederate nation.
Root also indulged in a bit of self-promotion by mentioning his own "The Battle Cry of Freedom" in the song.
"Just before the Battle, Mother" was recorded by Tennessee Ernie Ford on his album Tennessee Ernie Ford Sings Civil War Songs of the North which is where I learned it.
Other Civil War era songs in this collection are: