The Civil War Series, all eight novels by Joseph Altsheler
This Kindle book includes: The Guns of Bull Run, The Guns of Shiloh, The Scouts of Stonewall, The Sword of Antietam, The Star of Gettysburg, The Rock of Chickamauga, The Shades of the Wilderness, and The Tree of Appomattox. According to the original publisher, in the Civil War Series "Altsheler covers the principal battles of the Civil War. In four of the volumes Dick Mason, who fights for the North, is the leading character, and in the others, his cousin, Harry Kenton, who joins the Confederate forces, takes the principal part." According to Wikipedia, "Joseph Alexander Altsheler (April 29, 1862 - June 5, 1919), was an American author of popular juvenile historical fiction."