The story of the American Civil War: 32 key moments in the landmark conflict

As Abraham Lincoln was later to say, “all knew” that “somehow” slavery was the cause of the war. This is not the same as claiming that northerners and southerners went to war in 1861 with the desire to attack or defend slavery as a prime motivation: most did not. However, it became increasingly difficult to sustain a nation divided, “half slave and half free” in Lincoln’s phrase.

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Americans in 1861 had much in common with one another: a reverence for the Founding Fathers and a shared belief in freedom, opportunity and providential God. Most people, both north and south, worked on the land; almost all white folk assumed racial superiority, whatever their views on slavery. However, slavery shaped the south in ways that made the north see it as a threatening and alien society, just as northern attacks on slavery pushed southerners to see Yankees as their enemies.

Abolitionism versus proslavery

Slavery was a capitalist institution: it depended on ‘owners’ being able to buy, sell and invest in human beings. That in turn required confidence on the part of buyers that their ‘property’ would be protected and recognised. This was why the rising antislavery movement, with campaigners’ core claim that human beings could never be turned into mere property, was so threatening to slaveholders. Unlike other moral issues that enter politics, abolitionism threatened billions of dollars of investments. Most Americans in both sections shared the common aspiration of property ownership and believed they lived in an open, free society where hard work was rewarded. The difference was that most southerners were comfortable with the idea that black people were just another type of property.

In the 1830s, the abolitionist movement grew into a loud, if minority, force in the north. It was a transatlantic movement inspired by abolition in the British Empire, powered by evangelical fervour and horror at the human cost of slavery, not least in terms of the destruction of family life and the violation of women. From the 1830s onwards, the open discussion of emancipation in the south became impossible. Slaveholders needed the free states to recognise the legitimacy of their slave property. They tried, and briefly succeeded, to ban antislavery material from the US mail and to prevent the discussion of antislavery petitions in congress. They were caught in a cycle whereby, as more and more people denounced slavery, they needed ever-greater reassurances.

The Mexican War breaks out

In 1846, President James K Polk, a Democrat and a slaveholder, used a border dispute as a pretext to invade Mexico. Southerners were excited by the prospect of acquiring new slave territory but many northerners supported the war as well, assuming that it was the destiny of whites to settle the entire continent. The Mexican War was probably the most successful war of imperial expansion in modern history: a decisive and relatively low-cost victory for the USA that led, in 1848, to the annexation of the present-day states of California, Nevada, Utah, Arizona, New Mexico as well as parts of Texas and Colorado.

However, the war also set the nation on a collision course over slavery. Very few northerners were out-and-out abolitionists but most, it turned out, were against the expansion of slavery into these new territories in the west. Increasing numbers of northerners believed that if the new territories were allowed to become a ‘vast slave empire’ then the character of the nation would be changed forever, and the ‘right to rise’ for the honest white working man would be sacrificed in the interest of a slaveholding class. Free white men did not want to have to compete for land with privileged slaveholders. Nor did they want to end up competing as labourers against black slaves.

In the end, a compromise was struck: California was admitted as a free state (just as the Gold Rush made it a magnet) but most of the rest of the former Mexican land was opened to the possibility of slavery, should the local settlers so desire it.

The Fugitive Slave Act 1850

Among the reassurances demanded by southerners was a new Fugitive Slave Act, passed by Congress in 1850 against northern opposition, which aimed to make it easier for slaveholders to reclaim runaway ‘property’ in the free states. Ironically in view of southerners’ later protestations about states’ rights, the act led to a massive expansion of the federal government, giving it the right to override northern states’ law-enforcement procedures.

Southerners saw the law as a test of how far the north was prepared to accommodate what they called their ‘peculiar institution’. “Respect and enforce the Fugitive Slave Law as it stands,” one proslavery editor warned the north. “If not, WE WILL LEAVE YOU!” By demanding that freemen be shackled and returned to slavery against the wishes of the local community, the Fugitive Slave Act made a formerly abstract issue frighteningly real.

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A number of high-profile cases of allegedly runaway slaves being returned to bondage electrified the north. In 1854, thousands of Bostonians shouting “shame!” and “kidnappers!” watched in horror as Anthony Burns, a black man who had been living as a freeman in the city, was marched in chains by federal troops to the wharfside to be taken back south into slavery. This was the backdrop to the phenomenal popularity of Harriet Beecher Stowe’s famous novel Uncle Tom’s Cabin, a grim depiction of the harshness of plantation life that further raised northerners’ awareness of slavery.

Kansas-Nebraska Act 1854

Did railroads help cause the civil war? It was the desire to build a railroad to California that led Congress in 1854 to organise land to the west of Illinois, creating the territories of Kansas and Nebraska. This was land that had been part of the United States for half a century but had been barely settled by European Americans, and from which slavery had been banned under the terms of the Missouri Compromise in 1820.

Southerners in Congress only supported the bill once the prohibition on slavery was lifted. To millions of northerners, including many who had never previously considered themselves antislavery, this was a betrayal of a sacred promise that the lands of Kansas and Nebraska would be open to the free settlement of poor white men. More than that, it seemed to be evidence that the government was in the hands of sinister and ‘aristocratic’ proslavery interests.

The Kansas-Nebraska Act was the single most important catalyst for the rise of a new political party, the Republican Party, which presented itself as the only true defender of northern interests against the aggressions of the south. ‘The North is discovered!’ was one of many Republican campaign songs. If the party could unite the northern states, it could capture enough Electoral College votes to win the presidency even without having any support at all in the south.

It didn’t manage this in 1856. Hapless Pennsylvania Democrat James Buchanan won instead. But in the coming few years, the new party built support further as the south demanded even greater protection for its slave ‘property’.

The rise of Abraham Lincoln

Abraham Lincoln was born in 1809 in a log cabin in what was then the frontier state of Kentucky. Despite having virtually no formal education, Lincoln made his own way in life, shrugging off his subsistence-farming background and the whiskey-soaked roughness that went with it. He became a leading lawyer in Springfield, Illinois, and with a keen interest in politics, he also became a prominent state politician, arguing for transportation improvements and secure banks.

After one term in Congress in the late 1840s, his political career appeared to be over. But like many others, he thought the Kansas-Nebraska Act was a challenge that had to be faced. In a speech given at Peoria, Illinois, in 1854, Lincoln expressed the shame and anger so many northerners felt at the potential expansion of slavery. “Our republican robe is soiled and trailed in the dust,” he declared. “Let us repurify it. Let us turn and wash it white, in the spirit, if not the blood of the revolution.”

Although Lincoln repeatedly said that he disapproved of slavery as a violation of the rights of men to the fruits of their labour, he was not an abolitionist and he revered the American Constitution, even though it protected slavery within states that allowed it. But while he did not advocate the immediate overthrow of slavery, he said again and again that it should be placed “on the path to ultimate extinction”.

In Lincoln’s view, the United States would become either a slave nation or a modern free-labour nation. For the future president, the time had come to be clear about the final destination.

John Brown’s raid of 1859

In October 1859, the messianic abolitionist John Brown launched an amateurish raid on the federal arsenal at Harpers Ferry, Virginia. His aim was to distribute the arms among local slaves and spark a general insurrection. Brown was quickly apprehended by US troops under the command of Colonel Robert E Lee.

Brown’s raid struck southern society at its weakest point, but shocking as it was for white southerners that violence had been used on their home soil, the most frightening aspect of the affair was the northern response. While most mainstream politicians, including Republican leaders, condemned Brown’s acts, there was also admiration for his bravery. In antislavery strongholds, including Massachusetts, supporters raised funds for Brown’s legal defence and to help his family.

Brown played the part of martyr to perfection. Republican newspapers reported his well-aimed final words as he was led to the gallows: “I, John Brown, am now quite certain that the crimes of this guilty land will never be purged away – but with blood.” Brown’s raid reinforced southerners’ conception of themselves as victims. One Virginia newspaper concluded: “Thousands of men who, a month ago, scoffed at the idea of a dissolution of the Union… now hold the opinion that its days are numbered.”

The 1860 election

The trigger for secession was the election of the Republican presidential candidate Abraham Lincoln in November 1860. It was, in effect, two parallel elections, one in each section. The Democratic Party split, with one Democrat, Stephen

A Douglas, fighting Lincoln in the free states, while another, John C Breckinridge, fought for the votes of slave states against a more moderate third-party opponent. Lincoln won only 40 per cent of the national popular vote, but by winning almost all of the free states, he comfortably carried the Electoral College.

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Antislavery men welcomed Lincoln’s election as a decisive break with the past. The patrician Bostonian Charles Francis Adams was elated that “the great revolution has actually taken place” and that “the country has once and for all thrown off the domination of the slaveholders”.

In southern states, the so-called ‘fire eaters’, who had been campaigning for secession for years, appeared to have been prescient. Lincoln, like the rest of his party, believed slavery was wrong. To the leaders of southern society, this was enough for them to believe that the federal government had fallen into the hands of people who were their enemies. Irrevocably so, since the rising population of the free states meant their Electoral College advantage would only increase and leave the south politically impotent. “The election of Lincoln,” wrote one southern politician, “has placed our necks under their heels.”

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Southern states secede from the Union

To no-one’s surprise, South Carolina, long the most radical proslavery region of the southern states, was the first to announce it was leaving the Federal Union, on 20 December 1860. The resolutions adopted that day made it explicit that the motive was the protection of slavery. South Carolina secessionists condemned the free states for denouncing “as sinful the institution of Slavery”.

Elsewhere, ‘fire eaters’ gained political momentum, capturing popular indignation at Lincoln’s election. By 1 February 1861, Mississippi, Florida, Alabama, Georgia, Louisiana and Texas had passed secession resolutions. By 9 February, commissioners from the seven seceded states, meeting in Montgomery, Alabama, had adopted a provisional constitution and Jefferson Davis of Mississippi became the provisional president of the Confederate States of America.

Even so, the tide of secession was held back by Unionists in the upper south states of North Carolina, Tennessee and Arkansas. In Virginia, still the state with the largest number of slaves, secession was opposed by those counties with fewer slaves. Although not pro-emancipation, they argued that the Union, notwithstanding the election of a president who was a ‘Black Republican’, still provided more security for slavery than an untested southern Confederacy.

Conscious that Lincoln’s election had been entirely legitimate, some urged the southern states to wait for an ‘overt act’ of aggression.

That overt act soon came. By June 1861, 11 slave states formed the Confederacy and prepared to defend their independence.

Sumter and the outbreak of war, 1861

The first shots of the American Civil War were fired at 4.30am on 12 April 1861 by South Carolina forces. Their target was Fort Sumter, an island in Charleston’s harbour garrisoned by Union troops. Perhaps deliberately, the new president, Abraham Lincoln, had precipitated this aggression by making public his plan to re-supply (though not reinforce) the fort.

By opening fire on Fort Sumter, the Confederates played into Lincoln’s hands by making the issue a test of whether a free government could and would defend itself.

The shocking image of the stars and stripes under fire stirred the north in defence of the Union, overshadowing the slavery issue. Newspapers, which the day before had called for compromise and a cooling of passions, now called for vengeance and urged their readers to rally behind the flag.

On 15 April, Lincoln called for 75,000 volunteers under the 1795 Militia Act to serve for 90 days, the maximum amount prescribed by the law. This was the ‘overt act’ of aggression that prompted the states of Virginia, North Carolina, Arkansas and Tennessee to join their fellow southern slave states in seceding. With the seceded states making clear they were fighting for nothing less than independence, the Lincoln administration mobilised for a war to bring the rebels forcibly back into the Union.

Abraham Lincoln never recognised the Confederacy: to him these states were simply rebels and the war a giant police action to restore the authority of the national government. “Secession”, Lincoln insisted, was “the essence of anarchy”.

Key battles of the American Civil War

By 1861, the United States had been launched into a vicious civil war that would last four years – the next stage would be characterised by ferocious battles, with heavy defeats and hard-won victories for both sides...

Battle of Bull Run, 1861

One of the main reasons a political conflict turned to war was that, in 1861, the vast majority of Americans were not trying to seek an accommodation; they wanted a fight. A few wise heads on both sides knew that once war came it would be long and costly. For many, though, resorting to violence was not a sign of failure but a manly, healthy, possibly even purifying way of resolving an intractable conflict.

The Confederate government was established in Richmond, Virginia, less than 100 miles due south of Washington. Northern newspapers emblazoned, “Forward to Richmond!” atop their editorial pages. Volunteer troops gathered in Washington in their makeshift uniforms. On all sides the expectation was that one quick and decisive battle would probably decide the fate of the rebellion.

Instead, the first big confrontation between North and South was a chaotic battle outside Washington, near Bull Run creek, on 21 July 1861. The cavalry on both sides seemingly operatedat random, certainly without any proper co-ordination with infantry attacks. Troops mistook units on their own side for the enemy. After an inconclusive few hours of fighting, the Union army was sent into a panic-stricken retreat by a Confederate attack.

The losses in this first great conflict were tiny compared to the carnage of later battles, yet at the time casualty figures of 1,982 Confederate troops and 2,896 Union soldiers shocked both sides profoundly. While southerners rejoiced at victory, northerners were forced to confront for the first time the scale of the undertaking they had so blithely embraced.

Strategy and tactics

In grand strategic terms, the Union needed to be on the offensive in order to conquer the South. Yet the South took the offensive whenever it could. General Lee invaded Maryland and Pennsylvania in the summers of 1862 and 1863, taking the war onto northern soil, in part because there was huge popular pressure on both sides to be seen to be on the attack.

However, technological innovations gave defending forces much greater tactical strength. Whereas in the Mexican War the army was still using smooth-bore muskets, by 1861 the use of rifled muskets and new conical-shaped bullets called Minié balls greatly increased the accuracy of firepower from a longer range. Towards the end of the war, entrenchments and barbed wire – notably in the long siege of Petersburg – made the conflict resemble the Western Front in the First World War.

Nevertheless, offensives against well-defended positions could still succeed when commanders not only had a numerical advantage but were also prepared to be persistent and flexible – as Grant and Sherman proved in 1864, and as British generals on the Western Front learned after 1916.

The Union army and slavery

From the moment war began, abolitionists argued that a conflict caused by slaveholders could only be ended by ending slavery, the “taproot of the rebellion”. But other northerners vowed they wouldn’t support an ‘abolition war’. The official line from Lincoln was clear: this was a war to restore the Union, with no other aim.

Yet the reality on the ground in the south meant the Union army had to make de facto decisions about whether to encourage the dismantling of slavery. Wherever there was a Union military presence in a slave state, enslaved people sought sanctuary.

Some Union generals sent them back to their ‘owners’. Others allowed them to stay, and refugee camps grew up around military camps. It was General Benjamin F Butler, in command of a Union-held enclave in Virginia, who found a way of protecting runaway slaves without publicly challenging the official line that the Union did not seek emancipation. In the summer of 1861, he announced that any fugitive slave who sought refuge with his forces would be held as “contraband of war”.

This phrase deftly turned the argument that slaves were property against southerners. Just as horses or guns, if captured, could legitimately be impounded since they were likely to be of military value to the enemy then so too ‘human property’, likely to be used to dig fortifications or supply the Confederate army, could be seized – and effectively freed. Contraband became the normal term to describe runaway slaves for the rest of the war. As the debate about emancipation raged in the north, the reality was always that, intentionally or otherwise, the Union army was an instrument of emancipation.

Battle of Shiloh, 1862

Most of the press attention was on the eastern theatre of the war in Virginia. But in the first phase of the war, during the winter and spring of 1861–2, there was little action in the east as General-in-Chief George B McClellan, a man of enormous self-confidence who rejoiced in the moniker “the Little Napoleon”, painstakingly drilled and built up his troops.

Meanwhile in the west, Union commanders made big gains in a plan to force Confederate forces out of Kentucky and Tennessee, and then take control of the Mississippi River. In particular, General Ulysses S Grant was stunningly successful at putting this strategy into practice. He captured Fort Henry and Fort Donelson, opening up the southward-flowing Tennessee and Cumberland Rivers to the Union. These brilliant successes were followed, on 6–7 April 1862, by a major battle at Shiloh in south-western Tennessee. Grant’s forces were surprised by a Confederate force under Albert Sidney Johnston and PGT Beauregard but, in the bloodiest battle of the war to that point, the Union army held its ground, helped by the timely arrival of reinforcements.

The outcome of Shiloh was that a Confederate counter-offensive had been thwarted, albeit at heavy cost. Grant was initially criticised for his part in the battle, but when Lincoln was urged to remove him from command, he replied, “I can’t spare this man, he fights.”

The Trent affair

The greatest danger of war between Britain and the USA came from a conflict over the rights of British shipping. The US Navy tried to seize British merchant vessels bound for neutral ports near the Confederate coast, such as the Bahamas or Cuba, on the grounds that cargo was then to be transferred to southern blockade-runners. On occasion, the US succeeded. Britain had done much the same to American shipping during the Napoleonic Wars, and at the time the US had protested fiercely (the issue was one of the triggers of the war of 1812). Now the roles were reversed.

The conflict came to a head on 8 November 1861, when sailors from the USS San Jacinto boarded a British ship, RMS Trent, 300 miles east of Havana, and removed two Confederate envoys, James Mason and John Slidell, en route to Europe to press Britain and France for support. The British government was furious at the violation of its flag and there was talk of war. The diplomatic row was defused after US secretary of state William Seward apologised and released the envoys, insisting as he did so that the case proved that the British had finally accepted the United States’ conception of neutral shipping rights.

The larger issue was what role Britain might play in the war. Northerners were frustrated by British recognition of the South as a belligerent power (although Britain never gave the Confederacy diplomatic recognition) and angry about blockade-running ships and a couple of naval vessels that were built in British ports. The Confederacy for its part hoped the cotton embargo would precipitate European intervention of the kind that had tipped the balance for the rebels in the War of Independence. It never came.

The Peninsula Campaign

In the Peninsula Campaign of the spring of 1862, Union commander George B McClellan launched the Army of the Potomac in what he hoped would be the decisive move against the Confederacy. Rather than taking the direct approach due south, troops were sent by sea to the mouth of the James River from where they approached the Confederate capital Richmond from the east in a bid to evade Confederate defences. McClellan, who was fiercely opposed to emancipation, hoped to fight a limited war according to the “highest principles known to Christian civilisation”. At first the plan seemed to go well as Confederate forces fell back. But then General Robert E Lee took field command of the Army of Northern Virginia for the first time. An undemonstrative taciturn man, Lee was to about to prove himself one of the wiliest, most courageous and most effective commanders of the war. He believed the Confederacy could counter the manpower advantage of the Union army only by seizing and keeping the initiative.

In a stunning series of victories known as the Seven Days Battles (25 June–1 July), Lee’s leadership transformed the Confederacy’s position in one week, forcing McClellan’s army back. Thereafter officers and men in the Army of the Potomac developed what almost amounted to an inferiority complex in the face of Lee’s army, a spell that was only partially broken a year later at Gettysburg. McClellan’s star waned after the Peninsula Campaign and with him the idea the war could be fought in a ‘limited’ way.

Battle of Antietam, 1862

In September 1862, Lee launched the first of his two grand raids into the north. In optimistic moments, Confederate leaders hoped Lee’s invasion might persuade Maryland slaveholders to support the South and foreign powers to recognise it, but at the very least they wanted to prove the North could never subdue the South militarily.

The ‘invasion’ culminated in a battle at Antietam Creek near Sharpsburg, Maryland, on 17 September. The conflict was a fluid, confused and messy affair, with friendly fire compounding the difficulties of communication on a large battle area where no one had more than a partial view of the fighting. Particular spots on the battlefield acquired an especially gruesome reputation, including Miller’s cornfield, which changed hands six times in just a few hours, and ‘Bloody Lane’, a sunken road from which the rebel South held the attacking forces of the North at bay for over three hours in late morning.

By nightfall, at the cost of around 23,000 casualties, the Confederate line had been pushed back a few hundred yards. Still, it was a victory for the Union, although to Lincoln’s frustration McClellan failed to pursue Lee’s forces after the battle.

The Emancipation Proclamation

The limited Union victory at Antietam was to be the final battle of the first phase of the war. Just a few days later, on 22 September 1862, Lincoln issued a proclamation stating that if, by 1 January 1863, the rebel states of the Confederacy had not returned to the Union, the United States would, from that date onwards, regard slaves held in rebel areas as free. This Preliminary Emancipation Proclamation had an incendiary effect. It was an ultimatum to the South: return to the Union within 100 days with slavery intact, or face total destruction.

Confederate leader Jefferson Davis called it “the most execrable measure in the history of guilty man”. The three-month delay was intended to send a clear message that emancipation was a tool of war rather than an end in itself. Like a riot policeman giving notice that a mob was about to fired upon if it did not disperse, Lincoln wanted to give the appearance of due process. But no one had any illusions: the President had tied the Union’s fate to emancipation.

On 1 January 1863, the president duly issued the Emancipation Proclamation. It applied only to those areas of the United States that were still in arms against the government and much of the document was taken up with a list of counties in rebel states that, because they were no longer under rebel control, were exempted from the proclamation. Lincoln took a political and strategic risk in coupling together the fate ofthe Union with the fate of slavery.

In some Union regiments there were near-mutinies at the news. But abolitionists rejoiced that at last the day of jubilee was at hand.

Emancipation and racial attitudes in the Union Army

Union soldiers commonly used terms such as ‘darkie’ and ‘nigger’ in their letters. Even proudly antislavery soldiers exhibited an unquestioning racism. There was no contradiction in holding racist views while also thinking that a war against secession was inherently a war against slavery, and that the Confederacy was a repressive society that challenged American values of freedom and opportunity.

Encounters with runaway slaves had a dramatic impact on some Union soldiers. Black people were exotic and fascinating to rural farm boys from the north. In addition, many soldiers interpreted their encounters with freed slaves in the light of what they had heard and read of the cruelties of slavery. Private Chauncey Cooke wrote to his mother in Wisconsin about “a toothless old slave with one blind eye” who told him horrific stories of his wife and children having been sold, of whippings and being hunted by bloodhounds when he tried to escape. The stories, Cooke wrote, were “just like the ones in Uncle Tom’s Cabin and I believe them”.

Some Union troops were convinced by evangelical preachers and antislavery propaganda that expunging the sin of slavery would redeem their country in God’s eyes. Some simply wanted black troops to be placed in the front line instead of them. Most were probably convinced by the much more pragmatic case that if the rebels hated emancipation, then it must be a good thing, a weapon to strike at the heart of southern society.

Battle of Fredericksburg, 1862

After Antietam, General Ambrose E Burnside replaced George B McClellan as the commander of the Army of the Potomac. He assumed command of the army’s 120,000 men on 7 November 1862, and President Lincoln urged him to launch a fresh assault on Richmond immediately.

Burnside’s immense army was well supplied and even had hot-air balloons for surveillance, so he should have been able to outgun the Confederates. However it seemed that his troops could not out-manoeuvre the enemy. General Burnside’s plan was to cross the Rappahannock river above the town of Fredericksburg, which lay on the direct route from Washington to Richmond. A delay in the arrival of pontoon bridges meant that before the Union army had even crossed the river, General Lee had time to concentrate his troops on the heights behind Fredericksburg.

The Army of the Potomac eventually made it across the river on 13 December 1862, but could get no further. In repeated assaults up the gentle rise of Marye’s Heights, line after line of the North’s soldiers were cut down. The Union suffered more than 12,500 casualties in the day-long battle, and gained almost no ground.

Once the news of Burnside’s defeat at Fredericksburg broke, it seemed to inaugurate the bleakest period of the entire civil war for the North. President Lincoln summed up the Union’s perspective in one succinct line: “If there is a worse place than Hell, I am in it,” he told a visitor when the reports of the debacle came through.

Battle of Chancellorsville, 1863

On 30 April 1863, yet another Union commander, Joseph Hooker, crossed the Rappahannock River and tried to fight his way to Richmond. Hooker’s thinking was more subtle than Burnside’s – he crossed the river to the west of Fredericksburg with the aim of attacking the Confederates from the side – but the plan failed in its execution. Audaciously, Lee, ably supported by General ‘Stonewall’ Jackson, divided his army in the face of superior numbers and outflanked Union troops. In a three-day battle, Hooker made error after error, mistaking Jackson’s flanking movement for a retreat and finally abandoning the one piece of high ground from which artillery could be used effectively in wooded, undulating country.

The relief of victory for the South was tempered by the death of Jackson, who was accidentally fired on by his own men, prompting an outpouring of grief that transformed the dead general into a martyred hero. In retrospect, the battle of Chancellorsville was the high-tide mark of Confederate military success. It was certainly the apogee of Lee’s military career. Once again, his army had out-smarted and out-fought a larger, better-equipped Union force. But Hooker’s inept leadership had been a major factor in the southern victory, and such incompetence could not be relied upon indefinitely. The Confederates suffered huge losses and the difference in the size of the armies could be disguised by smart tactics only for so long.

Union victories at Gettysburg and Vicksburg, 1863

In the first days of July 1863, two simultaneous military victories for the Union seemed to turn the tide in the war. The Confederates had launched another raid into the north, this time up the Shenandoah Valley and into the state of Pennsylvania. General George Meade, the latest commander of the Army of the Potomac, led the forces that finally defeated Lee in a fight at Gettysburg during 1–3 July.

Lee’s army retreated back into Virginia but a spell of invincibility had been broken. Lee’s army never fully recovered from Gettysburg, in spirit or in numbers. His officer corps and command structure were hit especially hard. Never again in the war would Lee be able to rely on his officers as he had done in 1862. In 1864, he had to appear in person on the front lines to rally troops, which was something that he hadn’t done in previous years.

Meanwhile in the west, General Grant scored a major breakthrough. On 4 July, after more than six weeks, of failed assaults, Grant accepted the surrender of Confederate forces in the fortified river town of Vicksburg, the last Confederate stronghold on the Mississippi. With New Orleans having fallen the previous year after an assault from the sea, the South was now split into two halves.

The final phase of the American Civil War: all out war

With fighting concentrated in the southern states, the Union army waged all-out war, aimed at destroying the Confederacy's morale and crushing its capacity to wage war. As the conflict entered its final phase and the South put up determined opposition, both sides suffered huge losses...

New York City draft riots, 1863

Northerners on the home front may have been far from the sound of gunfire, but they still felt the impact of conflict. Few northerners opposed the war at the outset but, by 1862, two issues – emancipation and conscription – aroused fierce opposition. To many Democrats Lincoln was a tyrant, crushing the freedoms of Americans by pressing them into an abolitionist crusade.

The most dramatic incident of violent discontent took place in New York City on 13–16 July 1863. In some of the worst rioting in American history, thousands of workers, most of them poor Irish immigrants, rampaged through the city in a howl of rage against attempts to implement the draft. They targeted the visible property of the rich and the offices of Lincoln-supporting newspapers. They also launched indiscriminate attacks on the black population of the city, lynching them and burning an orphan asylum. The rioters’ targets reflected their perception of the Republicans destroying the white man’s republic as they had known it. The total death toll is unknown but was probably over a hundred. Order was restored by troops who marched north after the battle of Gettysburg.

In retrospect, the riots were a watershed. In mainstream magazines such as Harper’s, images of white men rioting to avoid fighting for the North in New York were deliberately contrasted with black Union soldiers launching a heroic failed assault on Fort Wagner near Charleston.

The old race-based conception of citizenship, to which many northerners still clung, had never faced such a severe challenge.

Gettysburg address

The most famous of Lincoln’s speeches was a two-minute address to dedicate the military cemetery at Gettysburg on 19 November 1863. Lincoln was not even the main speaker – he wound up proceedings after a two-hour oration from Edward Everett. But it’s Lincoln’s words that endure: “Four score and seven years ago, our fathers brought forth on this continent a new nation, conceived in liberty and dedicated to the proposition that all men are created equal.” The effect of this was to date the origins of the republic to the Declaration of Independence of 1776, with its grand preamble authored by Jefferson and appealing to the universal ideal of equality, rather than the more prosaic Federal Constitution of 1787. Lincoln was implying that the Constitution merely gave form to the nation, and that the nation mattered not as an end in itself, but as an embodiment of the ideals of equality and liberty. Echoing in secular language the Christian idea of a trial of faith, Lincoln went on to claim the civil war was a test of “whether that nation or any nation so conceived and so dedicated can long endure”. In little under 300 words, he went on to explain why the struggle and the sacrifice had a dignity and a purpose of universal and transcendent significance: “That this nation under God shall have a new birth of freedom, and that government of the people, by the people, for the people shall not perish from the earth.”

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Lincoln’s eloquence was noted at the time, but the reputation of his Gettysburg address has grown over the years, as Americans have sought to find an uplifting meaning in the slaughter of the war.

General Grant’s spring campaign, 1864

General Ulysses S Grant took command of all Union armies in early 1864 and adopted a harsh strategy designed to destroy the Confederacy’s capacity to wage war. The spring campaign of 1864 differed from those of the previous three years in two ways. Firstly, Union forces now had an even greater advantage of numbers in most confrontations. In addition, rather than retreating after a setback, Grant ordered his men forward. Experienced soldiers used to long periods in camp followed by occasional terrifying battles now faced what seemed like continuous marching and fighting.

In the battle of the Wilderness, which took place from 5 to 7 May near the site of Lee’s victory at Chancellorsville in Virginia, Union forces failed to dislodge Lee from his position. Sparks from the muzzles of thousands of rifles set the woods on fire and thousands of wounded men burned to death. In two days of fighting, the Union army suffered more than 17,000 casualties and the Confederates around 11,000.

At the battle of the Wilderness and in the bloody engagements of the following three months, the losses on the Union side were horrendous, but proportionally less than the South suffered. Grant, dubbed Butcher Grant by some in the north, had made the grim calculation that his Union army could withstand its losses more easily than the Confederacy.

The battles of Spotsylvania and Cold Harbor, 1864

Time and again as Grant attacked through rural Virginia, Lee moved his army quickly before establishing powerful defensive lines. The action moved in an arc east and south as Grant tried to get through Lee’s defences and Lee manoeuvred to keep his heavily outnumbered and outgunned army between Richmond and Union forces. At Spotsylvania Court House on 12 May 1864, the South repulsed the North in a particularly vicious battle. Both sides fought intensely, especially around the ‘bloody angle’, a U-shaped line of Confederate trenches that, by the end of the day, were filled with a mixture of blood, mud and corpses. Spotsylvania was essentially yet another defeat for the North. Grant had attempted to seize an important crossroads; Lee had beaten him to it and had then successfully, albeit bloodily, held off the Union’s assault.

But Grant refused to treat it as a defeat. Instead, he attempted another large-scale flanking movement to try to get between Lee and Richmond. Again, Lee anticipated the move. On 3 June, the Army of the Potomac was hurled against well-entrenched Confederate fortifications at Cold Harbor. More than any other civil war conflict, Cold Harbor was a harbinger of the horrific first day of the battle of the Somme. Most of the 7,000 Union soldiers who fell that day did so in less than an hour, as wave after wave of attacking troops were cut down.

The siege of Petersburg, 1864–85

The Army of the Potomac moved south from Cold Harbor and crossed the James River in another attempt to force Lee out from his trenches by flanking his army and seizing the key railroad junction at Petersburg, Virginia, just south of Richmond. Once again, before an assault took place, Lee realised what was happening and marched his army to thinly defended Petersburg with astonishing speed. Thousands of Union soldiers fell in futile efforts to dislodge the rebels from their earthwork entrenchments.

For the third year in a row, a Union army that set out in the spring with high hopes of crushing Confederate resistance in Virginia appeared by mid-summer to have stalled. Lee still had fewer troops, but Grant had lost more men – 64,000 casualties in two months – and morale sank. After numerous failed assaults in June, July and August 1864, the Union army bedded in for a siege of Petersburg, extending a line of trenches south and west around the city. Romantic notions of valour were tested against the ever-present danger of being shot by snipers and constant artillery bombardment. Reflecting that reality, troops built ‘bomb-proof’ shelters and zigzag trenches. As one Ohio soldier put it, “The spade is more powerful than the cannon.”

But battlefield defences could aid attackers, too, since they enabled forces to be pushed close to the enemy lines, from where an overwhelming raid could be launched. Nevertheless, it wasn’t until 2 April 1865 that Petersburg surrendered, on the same day the Confederates evacuated Richmond.

The fall of Atlanta and Sherman’s March

While Grant was entrenching outside Petersburg, Union forces under the command of General William T Sherman made a momentous breakthrough at Atlanta, which fell to Union forces on 2 September 1864. Under Grant’s command, Sherman had helped to rout the Confederate Army of Tennessee under General Braxton Bragg in the Chattanooga campaign which took place the previous October and November. Since then, Sherman had been pushing further into the Confederate heartland.

After Atlanta fell, Sherman’s army embarked on a march to Savannah on the Georgia coast and from there, in the new year of 1865, turned north into South Carolina. This march was in line with Grant’s strategic plan to move on all fronts simultaneously, thus stretching the South’s limited resources. Its purpose was to destroy not only the crops, factories and railroads that sustained the Confederate war effort, but also to break the will of the southern people to keep on fighting with a demonstration of the military supremacy of the North.

Sherman was blunt: “We cannot change the hearts of those people of the South,” he wrote, “but we can make war so terrible… [and] make them so sick of war that generations would pass away before they would again appeal to it.” Sherman proposed to cut loose from his supply lines and “move through Georgia smashing things to the sea”.

A holy war?

The American Civil War took place in a highly religious society – one in which both sides interpreted victory and defeat in terms of God’s pleasure or displeasure.

This religiosity was an essential component in the capacity of both sides to endure horrendous losses. Clergymen told their congregations that war was a test of faith. And if it was a chastisement for sin, it was also an opportunity for national redemption and purification. Secular nationalist ideas about the sacrifice of war marking a coming of age for the American republic – or the creation of the Confederate nation – were reinforced by the religious notion of soil made sacred by a baptism of fraternal blood.

The American Civil War took place in a highly religious society – one in which both sides interpreted victory and defeat in terms of God’s pleasure or displeasure

For many Confederates, faith was the basis of their nationalism. The Yankees were imagined to be infidels. Confederate suffering was evidence that God had singled them out as a specially chosen people. On the other side, many northerners came to believe that God’s purpose in creating such suffering must be as a punishment for slavery. In the great abolitionist anthem ‘The Battle Hymn of the Republic’, Christ is seen in the “watch-fires of a hundred circling camps” and in the “burnished rows of steel” of the soldiers’ bayonets. The Union army was the army of the Lord.

In his second inaugural address, Lincoln abjured any triumphalism and instead spoke of “this terrible war” as judgment on both sides for the offence of “American slavery”. Perhaps, he speculated, only when “every drop of blood drawn with the lash shall be paid by another drawn with the sword” would the war end.

The 1864 election

No one of prominence ever suggested suspending elections during the war: after all, northerners claimed to be fighting for free government. But at the same time, organised opposition to the administration was seen by Lincoln’s supporters as tantamount to treason.

In 1864, Lincoln ran for re-election against former general George B McClellan, whose Democratic supporters were united in opposition to emancipation but divided over whether to continue the war. For Republicans, the election was a test of loyalty to the national cause. “For four summers the loyal North has been firing bullets at the rebellion,” ran a typical editorial. “The time has now come to fire ballots.”

Lincoln gained 55 per cent of the popular vote in the November election. This was a convincing if hardly overwhelming endorsement. The strength of the Democratic vote, even in the face of a campaign branding support for McClellan as a vote for the rebels, was a measure of northerners’ discontent over the transformations the conflict had brought about.

But the victory was enough. It was a ratification of the policy of war until the South surrendered and a rejection of any alternative path of negotiations. What’s more, Lincoln had been elected on a platform that committed him to support the proposed Thirteenth Amendment ending slavery. It was the first time that a major party had run with what amounted to an abolitionist platform. Lincoln used the political capital from his victory to push Congress to pass the amendment before the war came to an end, thus clarifying the legal status of freed slaves and avoiding what would have been the legal challenges to the validity of the Emancipation Proclamation.

When did the American Civil War end?

Southern surrender at Appomattox, Virginia, 1865

After one final fling at the Union trenches outside Petersburg, Lee’s men retreated from one line of trenches to the next and escaped west across the Appomattox river. On 2 April, in anticipation of the fall of Petersburg, the Confederate government abandoned Richmond, setting its offices on fire, loading its treasury and archives into railroad cars and fleeing west. The following day the Confederate capital was in Union hands.

The half-starved remnants of the Army of Northern Virginia, now grossly outnumbered by the Army of the Potomac, were chased into the remote south-west corner of Virginia. On 8 April, Union cavalry overtook Lee’s army and captured three trainloads of desperately needed rations at Appomattox station. Lee and his men had finally come to the end of the road.

Grant and Lee met in the drawing room of a private home in the village of Appomattox Court House on the afternoon of 9 April. For a few minutes the two generals exchanged pleasantries. Then Lee brought them to the business at hand. Grant wrote out the surrender terms and Lee signed them. The two generals shook hands. Most Americans shared the assumption that the surrender of Lee’s army signalled the effective end of the war, even though Jefferson Davis remained at large, as did several other Confederate forces. Not until 2 June in Texas did General Edmund Kirby-Smith formally surrender the last of the major Confederate forces, but in reality Appomattox was the end. It marked not just the defeat of the South’s four-year experiment in independence, but of freedom and republican government as they had understood it.

Lincoln’s assassination, 1865

On the evening of Good Friday, 14 April 1865, President Lincoln and his wife Mary went to Ford’s Theatre a few blocks from the White House to attend a benefit performance of a popular British comedy, Our American Cousin, raising money for the play’s producer, who also performed in the show.

Well-known actor John Wilkes Booth, scion of a famous family of Shakespearean actors, entered the theatre by the stage door and made his way to the corridor outside the presidential box. A man of strong Confederate sympathies, Booth had cast himself in the role of avenging angel. Together with a coterie of peculiar friends, several of whom appear to have been mentally ill, Booth had hatched a vainglorious plot. The plan was originally to kidnap Lincoln, bind and gag him, but after the fall of Richmond it was decided to assassinate the president instead.

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Booth made his move at a quiet moment in the play. He fired a bullet into Lincoln’s head at close range, then leapt from the box onto the stage. Before the audience grasped what they had witnessed, Booth fled, only to die when Federal troops caught up with him.

Lincoln did not die instantly. He was carried across the road to a room in a boarding house where he lay until the early hours of the next morning, never regaining consciousness. With Mary convulsed with grief and news of the assassination spreading rapidly by telegraph, Lincoln’s cabinet colleagues gathered. They were present at his bedside when the president drew his last breath, at 7.22am on 15 April. Edwin Stanton broke the silence with the words, “Now he belongs to the ages.” Lincoln’s death allowed northerners to weep for all their dead. The slogans sewn on flags and black banners, “The memory of the just is blessed,” ensured that Lincoln stood in for many other private losses.

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Adam IP Smith is professor of US history at University College London (UCL).

This article first appeared in BBC History Magazine's 'American Civil War' special edition