At the outbreak of the Civil War, the United States suffered a near-fatal blow. Led by Robert E. Lee, nearly half of the West Point-trained United States Army officer corps defected to the Confederacy. The nation had to recruit, train, and deploy an expanded military but lacked a reservoir of trained military leaders. One result was the enactment of the Morrill Land Grant College Act, which mandated the inclusion of a course in military science—the forerunner of today's Reserve Officers' Training Corps (ROTC).
As soon as the war began, blacks outside of the rebel territory volunteered for the Army. Expecting a short war, Secretary of War Cameron rebuffed the offers. Although some Army leaders such as Major General John C. Freemont sought to recruit blacks as soldiers, the Lincoln administration countermanded such actions. Meanwhile, ironically, the Confederacy enjoyed the fruits of slave labor in constructing fortifications and related combat service support roles. By 1862, after important military setbacks, Congress lifted the militia law ban on blacks and approved their use as Union Army laborers.
Following the Emancipation Proclamation in September 1862, Massachusetts was permitted to organize the black 54th and 55th Massachusetts Infantry regiments. (The exploits of the 54th Massachusetts formed the basis of the motion picture Glory.) In May 1863, the severe manpower shortage forced the War Department additionally to approve organization of black regiments with all-white officers. The units were designated as United States Colored Troops (USCT).
Following the establishment of USCT regiments, blacks fought and died in every major Civil War action. For a period, they did so being paid $3.50 per month less than white troops; the money was termed a clothing allowance. In some units, black troops refused to accept the lesser pay. After vigorous protests by both black and white citizens, the 1864 Army Appropriations Act approved identical pay scales for all soldiers.
The passions of the civil war resulted in ignoring the then-emerging doctrines of land warfare on issues such as treatment of non-combatants and prisoners of war, doctrines that arose in Europe in the wake of the Napoleonic wars. The most serious documented breaches of land warfare law were committed by the Confederacy. The barbaric treatment of white Union prisoners of war at Andersonville Prison in Georgia, for example, retains military infamy. Black soldiers who fell into Confederate hands were either re-enslaved or summarily killed. One of the bloodiest such events was the Rebel butchery at Fort Pillow, Tennessee. Congressional Report No. 65, "Fort Pillow Massacre" (April 24, 1864), identified the rebel leader responsible as General Nathan Bedford Forrest. According to the report:
...the rebels commenced an indiscriminate slaughter, sparing neither age nor sex, white or black, soldier or civilian. The officers and men seemed to vie for with each other in the devilish work; men, women, and even children, wherever found, were deliberately shot down, beaten, and hacked with sabres; some of the children not more than ten years old were forced to stand up and face their murderers while being shot; the sick and wounded were butchered without mercy, the rebels even entering the hospital building and dragging them out to be shot or killing them as they lay there unable to offer the least resistance
Following the war, Forrest organized the Ku Klux Klan.
This nation's highest decoration for valor was established during the Civil War when Congress authorized issuance of a Medal of Honor on December 21, 1861. Issuance was initially limited to enlisted men of the Navy and Marine Corps, but the award was expanded to include the Army on July 12, 1862. On March 3, 1863, commissioned officers also became eligible for the Medal of Honor. During the war, 1,523 Medals of Honor were awarded, twenty-three of which were awarded to black servicemen. The first black recipient was Sergeant William H. Carney, 54th Massachusetts Infantry, for combat valor on July 18, 1863, at Fort Wagner, South Carolina.
By the end of the Civil War, more than 35,000 black troops had died—approximately thirty-five percent of all blacks who served in combat. The United States Colored Troops had constituted thirteen percent of the Union Army.