Sounds like one of my all-time favorites, "Two Brothers" which can be found on this site. It has the annotation (Civil War) after the title. I first heard this sung by Bud and Travis on a radio show in 1964. (I stumbled upon an old record album of theirs at a yard sale a couple of weeks ago - what a blast from the past!) I fell in love with it too. It has many of what are, in my view, the best elements of a folk song: simplicity, repetiton, tradgedy or joy, and a workable melody line. The only down side I can see with this song is its all-too-predictable ending. Many performers attempt to short-circuit this by simply stopping the song when they arrive at the last line of the part about the women at the railroad track "one wore blue and one wore black..." I think Bud and Travis, (being uptown folkies at best) end on a enigmatic 9th chord or somesuch.