By one of the nation’s foremost legal historians, a groundbreaking history of the pioneering American role in establishing the modern laws of war. In the fateful closing days of 1862, just three weeks before Emancipation, Abraham Lincoln’s top military advisors commissioned a code of rules to govern the armies of the United States in a newly intensified war effort. The code Lincoln issued the next spring helped shape the remaining two years of Civil War. Its rules on torture, prisoners of war, assassination, and more quickly became foundations of the modern laws of war and today’s Geneva Conventions. Yet the hidden story of Lincoln’s code, and of the decades of controversy that lay behind it, has never been told. In this masterful and strikingly original history, John Witt charts the alternately troubled and triumphant course of the laws of war in America from the Founding Founders to the dawn of the modern era, revealing the history of a code that reshaped the laws of war the world over. Ranging from the Revolution to the War of 1812, from war with Mexico to the Civil War, from Indian wars to the brutal counterinsurgency campaign in the Philippines, Witt tells a story that features presidents as well as men in the throes of battle, one that spans war-makers and pacifists, Indians and slaves. In a time of heated controversy about the nation’s conduct in the war on terror, Lincoln’s Code is a compelling story of ideals under pressure and a landmark contribution to our understanding of the American experience.