The Art of War
This novel is a depiction of the art of war, showing how Generals strategize and plan, showing the hierarchy of power amongst the ranks, showing how fatigue, exhaustion, and psychology all affect the outcome of battles (morale), and most of all, showing that on the battlefield, there is a sense of honor, poise, despite the unbridle horror of conflict.
The Civil War and Slavery
Some of the officers will occasionally muse about race, slavery, and the cause of the Civil War. This happens most notably when the Union runs into an escaped slave, causing Chamberlain to think deeply about these things. The Civil War is shown from both angles, at least militarily, but the issue of slavery is only condemned in the book, as well it should be.
Casualties and the loss of life
This retelling of the Gettysburg story focuses on the loss of life, especially when the Confederate forces discover that the Union is camped among the peach orchard, not in the mountain where they though. This means that the armies are within firing range, both sides are shocked to find. Many die here, and many more die in Pickett's charge into the center of Union forces.
