Context
By 1860, the United States faced an irreconcilable conflict over slavery’s expansion and the nature of federal union. The Missouri Compromise of 1820 and Compromise of 1850 had temporarily balanced free and slave states, but the Kansas-Nebraska Act of 1854 reignited sectional tensions by allowing popular sovereignty to determine slavery’s status in new territories. The Republican Party, founded in 1854 on an anti-slavery expansion platform, represented growing Northern opposition to slavery’s spread, while Southern leaders increasingly viewed any restriction as an existential threat to their economic and social order.
The election of Abraham Lincoln in November 1860, despite receiving no electoral votes from slave states, triggered the secession crisis. South Carolina seceded on December 20, 1860, followed by six other Deep South states by February 1861. These states formed the Confederate States of America, electing Jefferson Davis as president and adopting a constitution explicitly protecting slavery. Lincoln and most Northerners rejected secession as illegal, viewing the Union as perpetual and indivisible.
The immediate crisis centered on federal properties within Confederate territory, particularly Fort Sumter in Charleston Harbor. Confederate leaders demanded federal evacuation, while Lincoln sought to maintain federal authority without provoking war. Both sides mobilized troops and prepared for potential conflict, with four additional slave states—Virginia, Arkansas, Tennessee, and North Carolina—waiting to see whether compromise or confrontation would prevail.
The War
The war began on April 12, 1861, when Confederate forces bombarded Fort Sumter after Lincoln’s attempt to resupply the garrison. The attack galvanized Northern opinion and prompted Lincoln to call for 75,000 volunteers, which in turn triggered the secession of four Upper South states. The Confederacy relocated its capital to Richmond, Virginia, just 100 miles from Washington, D.C., setting the stage for intense fighting in the Eastern theater.
Initial expectations of a short conflict proved catastrophically wrong. The First Battle of Bull Run in July 1861 demonstrated that both armies were unprepared for large-scale warfare, while subsequent battles revealed the war’s unprecedented scale and lethality. In the Eastern theater, Robert E. Lee’s Army of Northern Virginia repeatedly outmaneuvered Union commanders, winning victories at Seven Days, Second Bull Run, and Fredericksburg. Lee’s invasion of Maryland ended at Antietam in September 1862, the war’s bloodiest single day with over 23,000 casualties.
The Western theater proved more favorable to Union forces under commanders like Ulysses S. Grant and William T. Sherman. Grant’s capture of Forts Henry and Donelson in early 1862 opened Tennessee to Union invasion, while his victory at Shiloh, despite horrific casualties, demonstrated Union determination to continue fighting. The siege and capture of Vicksburg in July 1863 gave the Union control of the Mississippi River, effectively splitting the Confederacy. Meanwhile, the Battle of Gettysburg (July 1-3, 1863) marked the war’s turning point, ending Lee’s second invasion of the North and beginning Confederate decline.
Lincoln’s Emancipation Proclamation, effective January 1, 1863, transformed the war’s meaning by making abolition a Union war aim. While freeing only slaves in rebellious areas, it prevented European intervention, encouraged slave flight to Union lines, and authorized black military service. Nearly 200,000 African Americans served in Union forces, providing crucial manpower and moral legitimacy to the Union cause. Grant’s appointment as general-in-chief in 1864 brought coordinated pressure on all Confederate armies, while Sherman’s March to the Sea devastated Confederate resources and morale.
Consequences
The war’s immediate aftermath saw Confederate surrender and the beginning of Reconstruction. Lee surrendered to Grant at Appomattox Court House on April 9, 1865, followed by other Confederate commanders over subsequent weeks. Lincoln’s assassination on April 14, 1865, just days after war’s end, complicated Reconstruction planning and elevated Vice President Andrew Johnson, whose policies would prove contentious. The Thirteenth Amendment, ratified in December 1865, constitutionally abolished slavery throughout the United States.
The war’s human and economic costs were staggering. Over 620,000 Americans died, with disease claiming more lives than combat. The South’s economy lay in ruins, with cities destroyed, railroads demolished, and agricultural systems disrupted by emancipation. The federal government emerged vastly strengthened, with expanded powers, a national banking system, and the transcontinental railroad. The Republican Party dominated national politics for decades, promoting industrial development and protective tariffs.
Reconstruction (1865-1877) attempted to rebuild the South and integrate freed slaves into American society. The Fourteenth and Fifteenth Amendments granted citizenship and voting rights to former slaves, while federal troops enforced civil rights laws. However, the Compromise of 1877 ended Reconstruction, leading to the rise of Jim Crow segregation and the systematic disenfranchisement of African Americans. The war’s legacy remained contested, with competing narratives of Union preservation versus states’ rights shaping American memory for generations.
Key Developments
- November 6, 1860: Abraham Lincoln elected president without winning any slave states
- December 20, 1860: South Carolina becomes first state to secede from the Union
- February 4, 1861: Confederate States of America formed with Jefferson Davis as president
- April 12, 1861: Confederate forces bombard Fort Sumter, beginning the Civil War
- July 21, 1861: First Battle of Bull Run demonstrates war will not end quickly
- April 6-7, 1862: Battle of Shiloh results in 23,000 casualties in Tennessee
- September 17, 1862: Battle of Antietam becomes bloodiest single day in American history
- January 1, 1863: Emancipation Proclamation takes effect, freeing slaves in rebel areas
- July 1-3, 1863: Battle of Gettysburg marks turning point with Confederate defeat
- July 4, 1863: Vicksburg surrenders, giving Union control of Mississippi River
- November 19, 1863: Lincoln delivers Gettysburg Address rededicating nation to equality
- March 12, 1864: Grant promoted to general-in-chief of all Union armies
- November 16, 1864: Sherman begins March to the Sea through Georgia
- April 9, 1865: Lee surrenders to Grant at Appomattox Court House
- April 14, 1865: Lincoln assassinated by John Wilkes Booth at Ford’s Theatre
- December 6, 1865: Thirteenth Amendment abolishing slavery ratified