The Most Devastating Battles of the Civil War

Since its founding, the United States has been shaped by its involvment in various wars, with each one bringing its share of death and destruction. However, no war fought on American soil has been as deadly as the Civil War. From 1861 to 1865, this brutal internal struggle claimed the lives of nearly 250,000 combatants from both sides, with total casualties estimated at around 620,000.

There were more than 10,000 military engagements fought during the war, of which 50 were major battles and 100 were significant ones. Battles were fought on both Union and Confederate lands, and each inflicted major losses. It should be noted that “casualties” include those killed in battle deaths but also those wounded, captured, or missing in action, as well as those who died away from the battlefield from accident or disease. (These are the states with the most Civil War deaths.)

To determine the deadliest battles in the American Civil War, 24/7 Tempo reviewed statistics on the data site Statista, which in turn obtained its information from the American Battlefield Trust, an organization that preserves America’s battlegrounds, and the U.S. Department of Defense.

The Battle of Gettysburg, taking place in the small town of Gettysburg, Pennsylvania was the site of the true turning point of the war. Not only was it a decisive battle that paved the way for the Union to eventually win the war, but it was also the deadliest. Over three days in early July 1863, the Union army under George G. Meade and Confederate forces led by Robert E. Lee waged a fierce battle.

In the end, the Union prevailed, but a total on both sides of more than 7,000 soldiers (and as many as 5,000 horses) were killed. By stopping Lee’s army from invading the North, the Union crushed the South’s hopes of a victory. (These were the largest battles of the Civil War.)

To determine the deadliest battles in the American Civil War, 24/7 Tempo reviewed statistics on the data site Statista, which in turn obtained its information from the American Battlefield Trust, an organization that preserves America’s battlegrounds, and the U.S. Department of Defense.

• When: May 18-July 4, 1863
• Total casualties: 19,233
• Fatalities: 1,611
• Which side prevailed: Union Army

Due to its location along the Mississippi River, Vicksburg provided an essential supply route for the Confederacy. The Union cut off that supply line by gaining control of the city. Abraham Lincoln termed the Vicksburg victory "the key to the war."

• When: Aug. 28-30, 1862
• Total casualties: 22,180
• Fatalities: 2,843
• Which side prevailed: Confederate Victory

The Second Battle of Bull Run (also known as the Battle of Second Manassas) proved to be a major victory for the South and General Robert E. Lee but it came at a cost of more than 1,000 Confederate lives. Lee's victory enabled him to take his army across the Potomac and into western Maryland, where he and McClellan would battle again at Antietam.

• When: Sept. 17, 1862
• Total casualties: 22,717
• Fatalities: 3,654
• Which side prevailed: Union Army

The Union declared victory in the bloodiest one-day battle in U.S. history until World War II. Despite the toll, the Union win gave Lincoln the victory he needed to release his Emancipation Proclamation.

• When: Dec. 31, 1862-Jan. 2 1863
• Total casualties: 23,515
• Fatalities: 2,971
• Which side prevailed: Union Army

Union forces led by Major General William Rosecrans clashed with the Confederate army commanded by General Braxton Bragg, and the two sides battled back and forth near Murfreesboro, Tennessee. On Jan. 2, 1863, Union forces achieved a much-needed victory.

• When: April 6-7, 1862
• Total casualties: 23,746
• Fatalities: 3,482
• Which side prevailed: Union Army

An early battle in the Civil War, the Battle of Shiloh in southwestern Tennessee was one of the deadliest. The battle gets its name from Shiloh Church near which the fighting occurred.

• When: April 30-May 6, 1863
• Total casualties: 24,000
• Fatalities: 3,418
• Which side prevailed: Confederate Army

The battle is famous for having been the last fought by Confederate General Thomas "Stonewall" Jackson, who was shot during the fighting and succumbed to pneumonia eight days later.

• When: May 5-7, 1864
• Total casualties: 29,800
• Fatalities: 3,723
• Which side prevailed: No side claimed victory

Newly appointed General in Chief of the Union Army Ulysses S. Grant confronted General Robert E. Lee in the dense woods in northern Virginia known as the Wilderness. The thick brush negated the Union's numerical advantage, but after two days of fierce fighting, the battle was considered a draw. Grant, however, refused to retreat and continued his march toward the Confederate capital of Richmond.

• When: May 9-21, 1864
• Total casualties: 30,000
• Fatalities: 4,240
• Which side prevailed: Inconclusive – both sides claim to have won

Over 12 days, Ulysses S. Grant's Army of the Potomac and Robert E. Lee's Army of Northern Virginia battled as both sides inflicted huge losses. But the battle was ultimately considered a stalemate as Grant disengaged his troops. Yet Grant kept up his march on the Confederate capital, forcing Lee to order his troops to deploy between the Union forces and Richmond.

• When: Sept. 18-20, 1863
• Total casualties: 34,624
• Fatalities: 3,969
• Which side prevailed: Confederate Army

The Army of Tennessee led by General Braxton Bragg initially defeated a force commanded by Union General William Rosecrans at Chickamauga, Georgia. When Bragg failed to build on the initial success, he allowed the Federal troops to reach Chattanooga. Reinforced by troops led by Ulysses S. Grant, the Union overtook Chickamauga, reversing what could have been a decisive victory for the South.

• When: July 1-3, 1863
• Total casualties: 51,000
• Fatalities: 7,058
• Which side prevailed: Union Army

The Battle of Gettysburg was the pivotal battle of the Civil War. Robert E. Lee's Army of Northern Virginia marched into the small town of Gettysburg, Pennsylvania where they clashed with Federal troops led by General George G. Meade. When Lee's troops failed to break the Union line at Cemetery Ridge, the Southern general retreated on July 4 and his advance on the North was halted.