The most transformative event in U.S. history, the American Civil War, tore the nation apart politically, socially, economically, and militarily. The causes of the war can be traced back to the creation of the country itself, and the war’s ramifications are still felt in American society today. The primary cause was the institution of slavery, which was a catalyst for ill-compromise between the north and the south for nearly fifty years that eventually unraveled into secession and war. What started the American Civil War? What were its causes? What were the significant events of the war? And how did the war affect American society?
Causes of the Civil War
The principal cause of the Civil War is slavery. The first compromises over this divisive issue occurred during the U.S. Constitution's creation during the Constitutional Convention. Later compromises will attempt to maintain a balance of political power between free and slave states that will only catalyze heated debates on defined partisan lines. The issue of slavery amplifies each secondary cause. The other conflicts that lead to the outbreak of war are sectionalism, abolitionism, federalism, economics, and the election of 1860.
Though each is tied to slavery, and some are interconnected, each in their way pushed the divide between the north and south to the breaking point.
Causes of the Civil War |
Cause | Union Perspective | Confederate Perspective |
Abolitionist Movement | Increasingly against slavery, by 1854, almost all northern states had legally abolished slavery. | The southern economy and society relied on slavery and saw the growing abolitionist movement as a threat to their culture and livelihoods. |
Sectional Conflict | Increasingly industrial economy - the need for tariffs to protect American industry | Agricultural economy - tariffs damaged their economy |
Federalism (State’s Rights) | Desire for a strong central government to regulate trade and commerce, and uphold minority rights | They wanted to maintain authority over their citizens and have the right to nullify federal laws in their states. |
Westward Expansion | With every new territory to the west, the debate of if it would allow slavery or not became a nationally debated issue. |
The Presidential Election of 1860 | Abraham Lincoln won the northern states; John Breckinridge won the southern states, suggesting a divided nation. Many southerners feared Lincoln would use his Presidency to push through laws abolishing slavery and removing states' rights in the federal government. |
The secession of the southern states | Once Lincoln won the election of 1860, the threat of secession from southern states was no longer a threat. In December 1860, South Carolina was the first state to hold a convention and secede. South Carolina was soon followed by Mississippi, Florida, Alabama, Georgia, Louisiana, and Texas. Following the attack on Fort Sumter in April 1861, Lincoln called for states to send 75,000 troops to be trained and sent to quell the “rebellious states.” With that proclamation, the following states seceded: Virginia, Arkansas, North Carolina, and Tennessee. |
Union: Twenty northern states and many states in the west that remained in the United States during the American Civil War
Confederacy: Also known as the Confederate States of America, consisting of 11 southern states that seceded from the control of the federal government of the United States, beginning with South Carolina in 1860
Secession: withdrawing from membership in the federal government
Tariff: tax on imports or exports
Outbreak of the American Civil War
As the southern states began to secede from the Union following Lincoln’s victory in the presidential election of 1860, there was a growing constitutional debate over whether or not the states had the right to do so. While this debate raged in Washington, Lincoln prepared to defend his own views- that states did not have the right to secede and that it was the federal government's role to ensure the Union remained with military force.
Fort Sumter
Fig. 1 - This painting depicts the attack on the Union Fort Sumter in Charleston Harbor on April 12, 1861
As the Union began to mobilize its military after Lincoln took office in March 1861, southern states, especially South Carolina, took note. When South Carolina seceded in December 1860, the state began to organize its militia. On April 12, 1861, South Carolina put the militia into military action, aiming the first shots of the American Civil War at Fort Sumter, a Union military garrison on an island at the mouth of Charleston Harbor that guarded the port of Charleston. Seeing the garrison as a means for the Union to block entry to the port, the Fort became the first and primary target of the South Carolina militia. After a two-day siege, the Fort still stood, but Union forces surrendered.
Battles of the Civil War
Following the attack on Fort Sumter, Lincoln called for 75,000 troops from the United States to help stop the growing rebellion in the south. With that proclamation, other states seceded, seeing the proclamation as an act of war on the sovereignty of the states themselves. As the Union continued to mobilize its armed forces, the southern states formed the Confederate States of America. They moved to combine the seceded states' military forces and some volunteer regiments from border states into an effective armed force to defend themselves from Union invasion.
With both armies poised to engage in July 1861, what would follow was nearly five years of horrific, bloody, and devastating warfare that would take place in three major theaters of war: the east, west of the Appalachian Mountains to the Mississippi River, and in the west through Missouri, Texas, and Arkansas - and claim more than 500,000 casualties. The table below highlights some of the significant engagements of the Civil War.
Major Battles of the Civil War |
Battle | Date | Victor | Significance |
First Battle of Manassas | July 21, 1861 | Confederacy | The first battle of the Civil War, also known as the First Battle of Bull Run, saw nearly 5,000 casualties and showed the leadership of both sides how bloody and deadly this conflict would become. |
Antietam | September 17, 1862 | Union | The single deadliest day in U.S. military history. Though a narrow Union victory, the single day of battle saw close to 23,000 casualties between both sides. |
Battle of Shiloh | April 6, 1862 | Union | One of the decisive battles of the Appalachian theater, the fighting saw an almost Confederate victory rapidly turn into a Union route for the southern forces. Over three days, with the bulk of the fight taking place on April 6, the battle took nearly 24,000 casualties from both sides. Significantly this battle marked a significant victory for General Ulysses S. Grant. |
Battle of Fredericksburg | December 11-15, 1862 | Confederacy | A resounding victory for the South that saw the Union take almost twice as many casualties as the south. This battle called into question the leadership of the Union Army and set the stage for General Robert E. Lee’s invasion of the north into Pennsylvania. |
Battle of Gettysburg | July 1-3, 1863 | Union | Arguably the most famous battle of the Civil War as it was the turning point of the war and the single deadliest battle in U.S. military history, with nearly 53,000 casualties. This battle would halt the Confederate invasion of the north and turn General Lee’s forces back to Virginia. Having sustained casualties that could not be recuperated, the Confederate forces began a defensive campaign with few victories. |
Battle of Vicksburg | May 18 - July 4, 1863 | Union | Usually overshadowed by the events at Gettysburg, the Battle of Vicksburg is arguably just as important a victory for the Union. After the Confederate forces under General John Pemberton surrendered to Union General Ulysses S. Grant, the war in the Appalachian theater was all but over as the Union now controlled the Mississippi River and the Tennessee River, cutting off central supply and transportation networks for the south. |
These are just some of the significant engagements of the Civil War. Overall, there were more than 10,000 military engagements and more than 50 significant battles between April 1861 and April 1865, when General Lee surrendered the Army of Northern Virginia, ending the war.
Civil War Military Strategies
The geographic, economic, and demographic differences between the Union and the Confederacy led to two different war strategies:
Comparing War Strategies of the Civil War |
Union | Confederate |
With a more significant population, a developed industrial complex that could produce weapons and ammunition at high rates, and a navy, the Union adopted a strategy called the Anaconda Plan. This plan would embargo the waterways, restricting access to needed materials, munitions, and food the southern states needed to conduct war. With a military blockade, the U.S. Army would push into the Confederacy to attempt to take the Capitol city (originally Montgomery, Alabama, and then later Richmond, Virginia) and divide the Confederate forces. | Initially, the Confederate Army devised a defensive strategy in which the Union could be portrayed as the aggressor, which was advantageous to the south gaining international support. Their defensive strategy was based on the fact that they had a smaller population, a deficit in manufacturing munitions, and no powerful navy. However, after the early successes at Manassas, Fredericksburg, and Chancellorsville, the south adopted an offensive strategy to invade the north through Pennsylvania, cutting off the Army from industrial cities and their supplies. |
The turning point of the American Civil War
Most historians agree that the Battles of Gettysburg and Vicksburg in 1863 marked the turning point of the American Civil War. With General Lee’s defeat at Gettysburg, his offensive push into the northern states ended. His Army of Northern Virginia took heavy losses in men and supplies that the Confederacy could not adequately replace. Because of this, General Lee is forced to retreat closer to supply lines in Virginia and establish a military campaign to defend the Capitol of Richmond.
Fig. 2 - This painting from 1887 depicts "Pickett's Charge", a pivotal moment of the Battle of Gettysburg that led to the retreat of Confederate forces
The Union, though also taking heavy losses at Gettysburg in 1863, had transformed its economy for war. Industrial centers and factories produced new and innovative weapons, munitions, artillery, and means of transportation. The larger population of the north also allowed most casualties to be replaced, not just replaced, but even with losses, the number of enlisted men in the Army grew each year.
With the victory at Vicksburg in Mississippi, the Union gained control of all significant waterways surrounding the Confederacy. This allowed them not only to cut off food and military supplies and limit the Confederate Army’s mobility but also allowed the Union to move its massive Army with minor harassment. In 1863, due to how the economics and demographics of the war had changed, a victory for the Union was inevitable; the only question the leaders of the Union and the Confederacy had to answer was how long they prolonged the bloodshed.
Leaders of the Civil War
Politically, the two leaders of the Union and Confederacy were Abraham Lincoln and Jefferson Davis, respectively. The Union and the Confederacy mainly went through several military commanders, but General Ulysses S. Grant and General Robert E. Lee were the most notable.
 Fig. 3- Abraham Lincoln, the U.S. President during the American Civil War
|  Fig. 4- Jefferson Davis, the President of the Confederacy during the American Civil War
|
 Fig. 5 - Ulysses S. Grant, the commander of the Union forces that ended the Civil War
|  Fig. 6 - Robert E. Lee, Commanding General of the Army of Northern Virginia and the commanding officer of the confederate forces in the eastern theater
|
Abraham Lincoln: the 16th President of the United States who won the election in 1860 and again in 1864. Under his leadership, the Union forces to victory in the Civil War. He expanded the federal government's power, preserved the Union through victory, and advanced the economy. He was famously assassinated on April 15, 1865.
Jefferson Davis: the President of the Confederate States of America. He implemented authoritarian control over the southern economy and military to consolidate the political, economic, and military power he felt necessary to defeat the Union. After the war, Davis lived in exile until 1869, when charges against him were dismissed.
General Ulysses S. Grant: Grant is the last of five commanding generals of the Union Army. He previously commanded the army in the Appalachian theater, and his success got him promoted to Commanding General in 1864 after several failed military campaigns from other generals. Under Grant's leadership and strategy, the main Confederate Army, the Army of Northern Virginia, was forced to surrender in April 1865. Grant will also serve as the 18th President of the United States from 1869 to 1877.
General Robert E. Lee: Commanding General of the Army of Northern Virginia, the largest Confederate Army. Respected by his opponents and praised by his army for his tactics, Lee oversaw the first successful years of conflict until the defeat at Gettysburg, when he changed his strategy to defend against the Union. Through his success and reputation, Lee holds influence over the commands of the other Confederate Army divisions and generals. Lee surrendered his army at Appomattox Court House on April 9, 1865.
Effects of the American Civil War
The war's immediate effects were physical and political. An estimated 530,000 to 650,000 men were wounded or killed during the years of conflict, more than the combined American casualties from World War I and II. Politically, the process of Reconstruction will see Congress and the President battle over federal power for nearly two decades. Other significant effects include:
Established the United States as a single sovereign entity
The emancipation of nearly four million enslaved Americans
Solidified the power and control of the central government over the states
Directly influenced the adoption of the following Amendments:
13th Amendment: Ended the practice of slavery in the United States
14th Amendment: All persons born or naturalized in the United States are U.S. Citizens - granted citizenship and protection under the Federal government to all freed enslaved persons
15th Amendment: Protects the right to vote for all U.S. Citizens
Began the Era of Reconstruction
The long-term effects of the Civil War can still be seen today in American society as political and social movements work to diminish the effects of Jim Crow laws established after the War in the South, protect voting and civil rights, balance issues of federalism, and lessen the effects of sectionalism in the modern United States.
The American Civil War - Key takeaways
- The most transformative event in U.S. history, the American Civil War, tore the nation apart politically, socially, economically, and militarily.
- The principal cause of the Civil War is slavery; the secondary causes are sectionalism, abolitionism, federalism, economics, and the election of 1860.
- Overall, there were more than 10,000 military engagements and more than 50 major battles between April 1861 and April 1865, when General Lee surrendered the Army of Northern Virginia, ending the war.
- The geographic, economic, and demographic differences between the Union and the Confederacy led to two different war strategies.
- The war's immediate effects were physical and political. An estimated 530,000 to 650,000 men were wounded or killed during the years of conflict, more than the combined American casualties from World War I and II. Politically, the process of Reconstruction will see Congress and the President battle over federal power for nearly two decades.
- The long-term effects of the Civil War can still be seen today in American society as political and social movements.
References
- McPherson, J. M. (2003). Battle Cry of Freedom: The Civil War Era (1st ed.). Oxford University Press.
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