Gods and Generals
Shaara, Jeff. Gods and Generals. New York : Ballantine, 1996.
A "prequel" to The Killer Angels. Gods and Generals follows four men during the years 1858-1863. Three will converge at Gettysburg: Robert E. Lee, Winfield Scott Hancock, and Joshua Chamberlain. The fourth, Thomas Jackson, won't quite get there.
Gods and Generals kicked off an enormously successful franchise of military novels by Jeff Shaara. It is somewhat less of an achievement than The Killer Angels, lacking that novel's focus and intensity. Also, all four protagonists seem to be pretty much the same person: a decent, somewhat bemused man, swept up in events where he seems to have no control and not even much volition.