Bubbling under the surface for decades and then raging for four years, the American Civil War was a brutal conflict between the anti-slavery Union in the north and the pro-slavery Confederacy in the south. Taking place between 1861 and 1865, it was arguably the first major war to be properly documented by photographers, and the emerging media captured the horrors of the conflict for the public and for future generations.

Click through this gallery to see the most startling snapshots from the American Civil War…

The national debate around slavery was at the heart of the American Civil War. Pictured here are abolitionists and escaped slaves at the 1850 Fugitive Slave Law Convention, which was held in Cazenovia, New York to protest the Fugitive Slave Act. The act empowered the government to capture escaped slaves even in free states, and obliged residents to cooperate with apprehension efforts. Several famous figures can be seen in this photo, including legendary escaped slave-turned-orator Frederick Douglass (seated, centre left) and Mary and Emily Edmonson (in plaid shawls), sisters who fled enslavement and joined the abolition movement.

A revolt led by abolitionist John Brown in 1859 was another key event in the run up to war. Under cover of darkness on 16 October, Brown led an armed raid on the federal armoury in Harpers Ferry, a riverside town (pictured) in what was then Virginia. The aim was to eventually establish a stronghold of escaped slaves who could fight the war against slavery. The raid was unsuccessful but it hugely inflamed tensions between the North and the South. Brown was captured and executed on 2 December in Charleston for murder and treason.

Writer and activist Harriet Beecher Stowe, pictured seated on the far right in this family portrait, is indelibly linked with the Civil War. Many of her relatives were social reformers and were active in the women’s suffrage and abolitionist movements. The Fugitive Slave Act struck a note with Stowe, partly inspiring her to write Uncle Tom’s Cabin, an anti-slavery novel published in 1852. It was hugely popular and helped drum up anti-slavery sentiment, creating sympathy with enslaved people. Stowe toured the country to promote the book and attended anti-slavery rallies.

Pictured here is the first inauguration of Abraham Lincoln, 16th president of the United States, which took place at the US Capitol (still under construction) on 4 March 1861 against a fraught backdrop of division and uncertainty. Seven southern states had already seceded from the Union at this point. And, just a month after Lincoln's swearing in, Confederate batteries fired on Union forces at Fort Sumter in Charleston Harbor, South Carolina, officially marking the start of the conflict.

Love this? Follow us on Facebook for travel inspiration and more

The shots fired at Fort Sumter on 12 April 1861 marked a pivotal moment in US history – the start of the ferocious four-year Civil War. The fort was in Charleston Harbor in South Carolina, which was the first state to secede from the Union in 1860 and was instrumental in the creation of the Confederacy. Following the Confederate capture of Fort Sumter, Virginia, Arkansas, North Carolina and Tennessee also left the Union, bringing the number of rebel states to 11. The Confederate flag can be seen flying above the captured fort in this image.

This photo taken by Mathew Brady shows a regimental drill being performed by the 96th Pennsylvania Infantry at Camp Northumberland, a Union encampment near Washington DC. An established portrait photographer, Brady and his team captured a wide range of important images during the war's early stages, from posed portraits of officers to the everyday lives of soldiers and the aftermaths of bloody battles. Images of the battles themselves were understandably not captured.

The First Battle of Bull Run, or the Battle of Manassas, was the first full-scale land battle of the Civil War, taking place in July 1861 by a small river named Bull Run near the town of Manassas in northern Virginia. It took place when General Irvin McDowell’s army of 35,000 men marched from Washington DC to capture Richmond, but they were defeated by a smaller Confederate force, a sobering loss for many Union supporters expecting an easy victory. Pictured here are the ruins of a bridge, taken soon after the battle.

With the conflict escalating, volunteers from both sides continued to enlist, and most soldiers were under 30 in both armies. Pictured here are off-duty soldiers preparing food on stoves in the tented camp of the 153rd New York Infantry, a regiment that was mustered in 1862. The regiment would endure dreadful trauma in the years to come, as more than 200 men were lost from the unit before it disbanded in 1865.

Sabre-wielding cavalry officers played a key part in the military campaigns. The Battle of Brandy Station, fought in 1863, was the largest cavalry battle of the American Civil War, with nearly 19,000 horsemen tearing up the battlefield. Confederate forces were surprised at dawn by Union cavalry under the command of General Alfred Pleasonton on 9 June in Culpeper County, Virginia. In a closely fought battle that raged over 14 hours, the Union suffered a slim defeat. The battle marked the start of General Robert E Lee’s Gettysburg Campaign, which would see him lead the Confederate Army into Pennsylvania. This photo shows Union cavalry and artillery in 1862.

Many enslaved people escaped to Union lines during the war. This image shows a Confederate soldier possibly guarding enslaved people at a plantation on Hilton Head, a barrier island in South Carolina. The estate was owned by General Thomas F Drayton, a planter and slave owner who became commander of the Confederate forces in the Port Royal District. The Civil War pitted families and friends against each other, and Drayton ended up defending Confederate forts against a Union ship captained by his brother, Percival Drayton.

This image shows Union soldiers surveying captured Confederates at a prison camp set up in the Shenandoah Valley following the Battle of Front Royal. Hundreds of thousands of soldiers were captured during the hostilities and often faced further brutality from their guards. More than 150 prison camps were established by the Union and Confederate armies during the war and it’s thought that approximately 50,000 prisoners died in captivity – an overall mortality rate of around 14%.

Taken near the battlefield of Bull Run in Virginia, this powerful image shows a group of children by a stream watching as cavalry from the Union Army give their horses water. Life was turned upside down for civilians in the frontline states as the war raged around them, and many, particularly in the South, experienced fighting first hand. As the men of each household went off to fight, the women and children faced regular curfews, and some saw their properties seized by occupying forces, never to be returned.  

Still the bloodiest day in all American history, the Battle of Antietam in Maryland took place on 17 September 1862 and saw 23,000 soldiers killed, wounded or missing in 12 hours of ferocious fighting. This image, taken by well-known Civil War photographer Alexander Gardner, shows President Lincoln visiting the battlefield two weeks later. Gardner had also taken stereographic images of the site two days after the battle, which scuppered Confederate general Robert E Lee's first attempt to invade the North.

As Union troops marched south, so too did photographers and reporters. They shared camps with soldiers, sending their stories via telegraph to newspaper editors in the cities. These reports would inform a captivated public about the troops' progress with graphic photos of war-torn towns and grim battlefields. Pictured here are journalists from the New York Herald in a Union Army camp. The Civil War was among the first wars to be properly photographed, a momentous event in the history of journalism and the way the public access information.

This stark image shows photographer Mathew Brady surveying the battlefield at Gettysburg following the most famous engagement of the Civil War. The Battle of Gettysburg – fought across three days in July 1863 – saw some of the war’s most gruelling combat. Both sides suffered devastating casualties, with 23,000 on the Union side and 28,000 for the Confederates. One enduring event was Pickett’s Charge, a disastrous frontal assault ordered by General Lee on the battle's final day that came with a casualty rate of almost 60%.

The earliest photos of America will amaze you

The vast quantity of wounded soldiers left by the Battle of Gettysburg led to the hasty assembly of one of the largest tent hospitals of the war. Known as Camp Letterman General Hospital, after Dr Jonathan Letterman, the medical director for the Army of the Potomac, it was set up on George Wolf's Farm just east of the battlefield with hundreds of hospital tents erected to treat wounded from both sides. Over 14,000 Union soldiers and 6,800 Confederate soldiers had been treated at the hospital by the time it closed, and more than 1,200 of these died.

The 47-day Siege of Vicksburg, which ended in July 1863 with a definitive Union victory, helped the North gain control of the entire Mississippi River, a success that Lincoln reportedly called "the key to the war". The capture of the Mississippi city was also an enormous boost for General Ulysses S Grant, the commander of the Union army during the latter years of the war. Hailed as a national hero after the Union’s victory, he would go on to become America's 18th president.

This image shows a crowd of people who'd fled from slavery as the divided country fought. Around 180,000 Black men, many of them former slaves who escaped from Confederate states, served as soldiers in the US Army during the hostilities, roughly 10% of the Union force. It’s estimated that 40,000 Black soldiers died during the war, after which around four million enslaved people were freed. For many, life after emancipation remained brutally difficult and many thousands died of hunger and disease.

This photo is a portrait of naval officers and crew on the deck of a gunboat, thought to be the USS Agawam, that was built during the Civil War by Union forces and used to blockade the James River in Virginia. Fought over throughout the war, the waterway was strategically important thanks to its position by the Confederate capital Richmond. The Confederate navy created the James River Squadron to defend the river from attacking Union warships during the conflict.

Brockenbrough House in Richmond, Virginia, became known as 'the White House of the Confederacy'. The grand mansion was the primary residence for Jefferson Davis and his family between 1861 and 1865, and was the seat of the Confederate government during the war. Davis, a planter, politician and soldier who was born in Kentucky and raised in Mississippi, was the first and only president of the Confederacy.

Captured by photographer Timothy O'Sullivan, this image shows Union troops using pontoon bridges to cross Germanna Ford, a natural crossing on the Rapidan River in Virginia. General Ulysses S Grant and his troops crossed this strategic spot several times during the war. Here they are pictured in May 1864 on the way to open the Virginia Overland Campaign – a protracted six-week offensive intended to defeat General Robert E Lee’s Army of Northern Virginia.

It wasn't all about fighting. This insightful photo shows the 50th New York Engineers building a road on the south bank of the North Anna River in Jericho Mills, Virginia, and was taken during Grant’s Overland Campaign. Army engineers, many of them volunteers, were a core part of the Union’s campaign to outsmart the enemy and break down Confederate defences. They helped troops cross waterways, penetrated enemy fortifications, destroyed and constructed railroad bridges and shored up defences in strategic locations.

Cramped conditions, dodgy sanitation and boredom characterised camp life for soldiers during the Civil War. This image shows tents and cabins in a Union Army camp at Brandy Station in April 1864. In the early stages of the war camps were set up with tents, but as the fighting continued more permanent camps like this one were constructed, sometimes with log cabins and chimneys. This required huge quantities of timber, and Virginia in particular saw huge stretches of woodland destroyed.

General William Tecumseh Sherman and his Union forces captured the southern city of Atlanta – a key supply centre and railroad hub for the Confederacy – in 1864. This photo shows a camp established by Union troops, thought to be the 2nd Massachusetts Infantry, in the grounds of the state capital’s City Hall. What’s known as the Atlanta campaign raged for most of the summer, and was a devastating blow to the Confederate cause.

General Sherman (centre) is pictured here with key officers around the time of the siege of Atlanta, which he spearheaded with the approval of Commander Grant. Sherman became famed for his so-called 'March to the Sea', which would see him and his 62,000 men carve a path across Georgia for 37 days starting in 15 November. They trudged 285 miles (458 km) east from Atlanta to Savannah, pursuing a scorched earth policy that left much of the land ransacked. After the war Sherman succeeded Grant as commander-in-chief of the US Army.

This photograph depicts one of Atlanta's many grand antebellum homes that was abandoned and left in ruins, and was taken by photographer George N Barnard. Much of the city was razed to the ground after Sherman ordered his troops to destroy industrial and military facilities in November 1864. Munitions factories, clothing mills and railway yards were set alight and the blaze spread, devastating residential areas too. Within a few days the fires had destroyed an estimated 40% of Georgia's capital.

One of the epicentres of the Civil War and a longstanding slave trading hub, Charleston in South Carolina was finally seized by Union forces in February 1865. General Beauregard ordered the evacuation of the city on 15 February, but commanded his troops to set fire to warehouses across the already-ravaged city to stop the Union forces restocking. This poignant photo, again taken by Barnard, shows a man sitting alone amid the rubble.

The Confederate headquarters in Richmond, Virginia, fell soon after, with fleeing troops setting fire to their one-time capital on 2 April 1865. It ended four years of Union campaigns against the city, and was the final act of General Grant's relentless 1864 Overland Campaign. Lincoln visited the smoking city two days after the Confederates left, including the house that had once been occupied by Jefferson Davis.

This portrait depicts John Wilkes Booth, one of the most notorious men in American history. With the Civil War barely over, President Lincoln was fatally shot by Booth, an actor and Confederate sympathiser, while watching a play at Ford's Theatre in Washington DC on 14 April 1865. A huge manhunt ensued and Booth was shot and killed while hiding out at a farm in Virginia. Several of his accomplices were later executed, including boarding house owner Mary Surratt, the first woman executed by the US government.

After fleeing Richmond with his cabinet, and hearing of the surrender of General Lee on 9 April, Confederate president Jefferson Davis was finally apprehended by Union cavalry along with his wife on 10 May near Irwinville in Georgia. Davis was imprisoned at Fort Monroe in Virginia, but he was never tried for treason and was released in May 1867. He travelled Europe with his family before returning to the American South.

Now discover the most powerful photos in US history