Nearly 13,000 Union soldiers died inside the confines of a single Confederate prison camp in Georgia, a place built to hold only a fraction of that number. While the Civil War is often remembered through its great battles and heroic generals, the conflict also produced a series of atrocities that left deep scars on the nation. From mass executions to the deliberate burning of civilian towns, these events reveal a darker side of the war that is often overshadowed by tales of honor and strategy. On April 12, 1864, Confederate cavalry under the command of Nathan Bedford Forrest attacked Fort Pillow, a Union garrison perched on a bluff above the Mississippi River.
Roughly half of the 600 Union defenders were Black soldiers from the United States Colored Troops, many of them former slaves. Confederate policy did not recognize these men as legitimate soldiers, meaning capture could result in execution or re-enslavement. When the fort fell, Union soldiers attempted to surrender, but witnesses reported that Confederate troops continued firing. Black soldiers were reportedly hunted down and shot as they ran or begged for mercy, with some killed by bayonet or burned to death in buildings set ablaze.
Nearly 300 Union soldiers were killed, most of them Black, and many after the battle was effectively decided. The massacre sparked outrage across the North, prompted a congressional investigation, and led many Union soldiers to adopt a policy of no quarter toward Forrest’s men. Deep in Georgia, the prison known as Andersonville became a slow-moving catastrophe. Officially called Camp Sumter, it was designed to hold 10,000 prisoners but at its worst held more than 32,000.
The open-air stockade offered no shelter, sanitation, or adequate food, and its single stream became a source of disease as prisoners drank, washed, and disposed of waste in it. Men grew skeletal, and bodies were dragged to the gate each morning in numbers that sometimes reached 100 per day. Nearly 13,000 Union soldiers died there, roughly one in three prisoners. After the war, the camp’s commander, Henry Wirz, was arrested and tried for war crimes, including deliberate starvation and murder through neglect.
He was found guilty and executed in 1865, one of only a few men to face justice for Civil War atrocities. By the summer of 1864, the war had become a cycle of retaliation. In July, Confederate cavalry under John McCausland rode into Chambersburg, Pennsylvania, a defenseless town of civilians. McCausland demanded $500,000 in gold or $100,000 in greenbacks, a sum the townspeople could not pay.
Acting on orders, his troops proceeded to burn the town. Soldiers moved street by street with torches, setting homes, shops, and barns ablaze. More than 500 buildings were destroyed, and thousands of residents were left homeless. It was the only northern town deliberately burned by Confederate forces during the war.
Missouri, already torn apart by guerrilla warfare, witnessed further brutality on September 27, 1864. Confederate guerrillas under William Quantrill and his lieutenant Bloody Bill Anderson stopped a train near Centralia, boarded it, and removed 22 Union soldiers, most of them unarmed and recently discharged. The guerrillas forced the men off the train, stripped them, and shot them one by one. Later that day, a Union cavalry unit pursuing Anderson’s men rode into an ambush.
Roughly 150 soldiers were slaughtered, and many of the dead were scalped. The bodies were left in a field as a warning. A year earlier, guerrillas under Quantrill had carried out an even deadlier attack on civilians. On August 21, 1863, roughly 450 Confederate guerrillas rode into Lawrence, Kansas, a town known as a stronghold of anti-slavery sentiment.
At dawn, they shot men in the streets, dragged others from their homes and killed them in front of their families, and looted and burned buildings. By the time they rode away, about 150 men and boys were dead, and the town lay in ruins. It remains one of the deadliest civilian massacres in American history. The aftermath of a battle in Virginia brought another deliberate slaughter.
On October 2, 1864, Union forces attacked Saltville, a town vital to the Confederacy because of its salt works, essential for preserving meat for the army. Among the attacking troops were Black soldiers from the United States Colored Troops. The Confederates drove the Union forces back after a brutal fight, leaving bodies scattered across the hillsides. As the guns fell silent, Confederate irregulars and soldiers, including men connected to the notorious guerrilla leader Champ Ferguson, moved across the battlefield.
They found wounded Union soldiers, many of them Black, lying helpless. Witnesses later testified that the wounded were shot one by one, with even white Union officers not spared. Some were killed inside hospital tents. Ferguson was captured after the war, tried before a military tribunal, and hanged in 1865.
In October 1862, a different kind of execution took place in Palmyra, Missouri. After a Union loyalist named Andrew Allsman disappeared near town, Union commander John McNeil issued an ultimatum: if Allsman was not returned within 10 days, 10 Confederate prisoners would be executed. Allsman never returned, and McNeil kept his word. Ten Confederate prisoners, most of them young, were blindfolded and shot by a firing squad.
Southerners called it murder; Union supporters called it justice. Historians still debate the morality of the act. While the Battle of Gettysburg raged in July 1863, New York City erupted in violence over the federal military draft. Working-class citizens, angry that wealthy men could buy their way out of service, rioted across the city.
Crowds burned buildings and attacked police before the violence turned racial. Black citizens were hunted in the streets. One mob captured an enslaved man named Abraham Franklin, beat him, dragged him through the streets, and lynched him from a lamppost. The mob also attacked the Colored Orphan Asylum, home to more than 200 children, though most escaped before the building burned.
The violence left at least 120 people dead and remains the deadliest riot in American history. In February 1864, Union Colonel Ulric Dahlgren led a raid toward Richmond with goals that included freeing Union prisoners and possibly assassinating Confederate leaders. The raid failed, and Dahlgren was killed during the escape. Confederate troops searching his body claimed to find documents ordering the assassination of Jefferson Davis and the burning of Richmond, though historians still debate their authenticity.
The Confederate response was harsh: captured raiders were imprisoned, some executed as spies, others held in brutal conditions. The affair hardened Confederate attitudes toward captured Union soldiers. General William Tecumseh Sherman’s March to the Sea in 1864 brought total war to the civilian South. Sherman believed the only way to end the war quickly was to destroy the South’s ability to fight.
His troops tore up railroads, burned factories and warehouses, emptied plantations, and slaughtered livestock. Foraging soldiers swept across the countryside, and many civilians lost everything they owned, leaving entire communities starving. Sherman called it strategy, but for countless Southern families, it felt like war waged directly upon them. Union prisons had their own horrors.
Near New York City, the USS North Carolina, a floating prison, held captured Confederate soldiers below deck in suffocating conditions. Disease spread quickly, food was scarce, and mortality rates soared. Hundreds died before the war ended. While Andersonville became infamous, suffering was not limited to one side.
The era’s violence also extended beyond the North-South conflict. On November 29, 1864, U. S. forces under John Chivington attacked a peaceful Cheyenne and Arapaho village at Sand Creek in Colorado.
More than 150 people were killed, many of them women and children. Bodies were mutilated, and scalps were taken as trophies. Though not part of the main Civil War conflict directly, it reflected the brutal mindset spreading across wartime America. In Richmond, Libby Prison held Union officers under harsh conditions.
Food was minimal, medical care was almost nonexistent, and cold winters and disease killed many. Some prisoners attempted daring escapes, but many simply wasted away within the prison walls. The Civil War was not only fought on battlefields.
These events, from massacres and executions to the deliberate destruction of civilian life, show what can happen when a nation turns its weapons and its anger against itself.