Why did the conventional wisdom —that soldiers become increasingly cynical and disillusioned as war progresses— not hold true in the Civil War? It is to this question —why did they fight— that James M. McPherson, America's preeminent Civil War historian, now turns his attention. He shows that, contrary to what many scholars believe, the soldiers of the Civil War remained powerfully convinced of the ideals for which they fought throughout the conflict.

McPherson draws on more than 25,000 letters and nearly 250 private diaries from men on both sides. Civil War soldiers were among the most literate soldiers in history, and most of them wrote home frequently, as it was the only way for them to keep in touch with homes that many of them had left for the first time in their lives.

Significantly, their letters were also uncensored by military authorities and are uniquely frank in their criticism and detailed in their reports of marches and battles, relations between officers and men, political debates, and morale. For Cause and Comrades lets these soldiers tell their own stories in their own words to create an account that is both deeply moving and far truer than most books on war.