Henry Fleming
Referred to as "the youth" throughout the novel, Henry is the protagonist. He joined the army with preconceived notions of the inherent glory of war. But the reality of the battles leaves him desperately afraid. In his first battle with the 304th regiment, he flees. His shame prompts him to return and he eventually fights courageously in his second battle. His musings, thoughts, and responses to war are the focus of the book; because of his changing minds and deeds, he matures as the book progresses. He is, at times, arrogant, prideful, cowardly, courageous, and obsessive.
Wilson
He begins the book headstrong and proud but through battle gains tranquility and wisdom. At first he is referred to as "the loud soldier" for his brashness, and then as "the friend" when he becomes close with Henry. He takes excellent care of Henry when he returns to the regiment and fights bravely in battle the next day. He captures the enemy's flag at the end of the novel.
Jim Conklin
Known as "the tall soldier," a friend of Henry's from home. Confident, he converses and argues with Wilson before the first battle begins. During his journeys after deserting, Henry encounters Jim in a procession of wounded soldiers. Gravely wounded, Jim appears to him as "the spectral soldier." Henry watches him die, unable to help his friend.
The tattered soldier
One of the wounded soldiers. He tries to chat with Henry about the battle and about Henry's wounds. His questions make Henry so upset and guilty that he runs away from him, leaving the tattered man stumbling in a field. At the end of the novel, Henry feels great shame for abandoning the tattered man.
The young lieutenant
Identified only through dialogue as Lt. Hasbrouck, the young lieutenant is the commander of Henry's regiment. He is shot in the hand in the first battle and in the arm in the second. He tries to get his men to fight and charge when they are braced with fear. Even when all he can do is curse at his troops, it is clear he may be crass, but he is brave. The young lieutenant's appraisal for Henry's aggressiveness boosts Henry's confidence.
Henry's mother
She does not approve of her son's enlisting, but does not prevent him from going. She only tells him to do what he thinks is right instead of telling him to be a hero.
The cheery soldier
After Henry is accidentally wounded, the cheery soldier leads him through the forest back to his regiment, chatting all the way. At camp it occurs to Henry he had not seen the man's face. Some theorize that the cheery soldier is Jim Conklin's ghost.
The general
Henry overhears the general speaking to an officer from his regiment. He nonchalantly says that many of the troops will not survive the next charge. After the unsuccessful charge, the general criticizes the regiment. Henry's anger at the man's derision motivates him to act in the next battle.