Dan Butterfield played a pivotal role during the Civil War. He led troops in the field at the brigade, division, and corps level, wrote the 1862 Army field manual, composedTaps,and served as the chief of staff for Joe Hooker in the Army of the Potomac. He introduced a custom that remains in the U.S. Army today: the use of distinctive hat or shoulder patches to denote the unit to which a soldier belongs and was a Medal of Honor winner. Butterfield was also controversial, not well-liked, and tainted by politics. Award-winning author James S. Pula unspools fact from fiction to offer the first detailed and long overdue treatment of the man and the officer in Major General Daniel Butterfield: A Civil War Biography.Butterfield was born into a wealthy New York family whose father co-founded American Express. He was one of the wars early volunteers, fought at First Bull Run, and made an important contribution with his Camp and Outpost Duty for Infantry (1862). He gained praise leading a