Aside from the slavery issue, The Killer Angels doesn't address in-depth political aspects. It primarily retells the unfolding events of the epic Battle of Gettysburg--the bloodiest ever on American soil. Col. Joshua Chamberlain's prime motive is to free the enslaved.
"This is a different kind of army. If you look at history, you'll see men fight for pay, or women, or some other kind of loot...or land... or just because they like killing. But we're here for something new... this hasn't happened much in the history of war. We're an army going out to set other men free."
Although this was not foremost in Abraham Lincoln's mind (his goal was to reunite the divided Union), this aspect is not discussed at length. Instead, the author sticks to the military analysis of the battle and the emotions of the men who are fighting it.
There are a multitude of heroic and tragic characters. Gen. John Reynolds turns down command of the Union army because he refuses to become embroiled in the political maneuvering of Secretary of War Edwin Stanton and Gen. Henry Halleck. (Gen. George Meade is named instead.) Reynolds oversees the initial troop placements, effectively deciding that the battle will unfold at Gettysburg, before he is shot dead by a Confederate sniper on the first day.
The fictional Buster Kilrain (whose name was created from the title, KIL-leR AN-gels) is also a tragic hero. Previously demoted from sergeant to private for assaulting an officer, he is nevertheless a valued member of Chamberlain's staff. He dies from his wounds, refusing medical aid so that others with more serious injuries can be treated.
Chamberlain is the central focus and most heroic character--both in the novel and historical terms. A former teacher and unprofessional soldier, Chamberlain refuses to execute a number of men who had previously deserted; instead, he gives them a second chance to redeem themselves on Little Round Top. He preaches to the men about self-sacrifice and the importance of being free. His heroic stand and brilliant military maneuvering with a skeleton force on Little Round Top saves the day for the Union and routs a crack Confederate brigade that has been ordered to take the hill. Chamberlain is gravely wounded and not expected to survive, but he recovers and is later awarded the Medal of Honor. The man who Chamberlain replaces, Col. Strong Vincent, is also a tragic hero: He is mortally wounded after recognizing the importance of Little Round Top and independently placing his men upon the hill.
Southern tragic heroes abound. Gen. George Pickett's division is decimated on the third day during its legendary assault on the Union center. Nearly all of his brigade and regimental commanders are killed or wounded, and Pickett loses about two-thirds of his unit. The bloody end erases the invincible aura that surrounds Gen. Robert E. Lee, and his once mighty Army of Northern Virginia never regains its prior clout. Lee's "Old War Horse," Gen. James Longstreet, had his reputation forever tarnished by the battle. However, historians agree that had Lee listened when Longstreet begged Lee to avoid battle and set up a strong defensive position elsewhere, the Battle of Gettysburg may never have happened. Longstreet's belief in strong defensive positioning--instead of Napoleonic-style frontal assaults--led to a change in Lee's later tactics as well as future American military strategy.