The election of Abraham Lincoln (November 1860) triggered secession! Lincoln was the first Republican president, and his party was founded on opposing the expansion of slavery into western territories. Southerners feared that if slavery could not expand, the slave states would eventually be outnumbered and slavery would be abolished. South Carolina seceded on December 20, 1860, followed by Mississippi, Florida, Alabama, Georgia, Louisiana, Texas, Virginia, Arkansas, North Carolina, and Tennessee. The Civil War began on April 12, 1861, when Confederate forces attacked Fort Sumter in Charleston Harbor, South Carolina. The war would last four years and claim over 600,000 American lives – more than any other war in U.S. history.

The Emancipation Proclamation freed enslaved people in Confederate-held territory! It took effect on January 1, 1863. The proclamation did not free enslaved people in border states (like Kentucky, Missouri, Maryland, Delaware) or in Union-controlled areas of the South. However, it fundamentally changed the nature of the war: the Union was now fighting to end slavery as well as to preserve the Union. It also allowed Black men to serve in the Union Army – over 180,000 Black soldiers fought for the Union by the war's end. Lincoln later worked to pass the 13th Amendment (abolishing slavery nationwide), which was ratified after his death, in December 1865.

Jefferson Davis was the Confederate president! He was a West Point graduate and hero of the Mexican-American War. Despite his military experience, he often clashed with his generals, especially Joseph E. Johnston. Davis struggled to manage the Confederacy's war effort with limited resources. The Confederate capital was Richmond, Virginia (moved from Montgomery, Alabama). The Confederacy was never recognized as a nation by any foreign government, though Britain and France considered it for economic reasons (cotton). After his capture, Davis was held at Fort Monroe, Virginia, for two years. He never faced trial – the federal government dropped the treason charges in 1869.

Ulysses S. Grant was the Union commander! Grant was known for his aggressive tactics and willingness to fight – critics called him a "butcher" for the high casualties his army suffered, but Lincoln supported him, saying "I cannot spare this man; he fights." Grant's Vicksburg campaign (May-July 1863) gave the Union control of the Mississippi River, splitting the Confederacy in two. The fall of Vicksburg on July 4, 1863, combined with the Union victory at Gettysburg the day before, marked the turning point of the war. Grant later became the 18th president, serving two terms. His face appears on the $50 bill.

The Battle of Gettysburg was the turning point! Fought in southern Pennsylvania, the three-day battle was the largest ever fought in North America, with about 160,000 soldiers and 51,000 casualties. On the third day, Lee ordered Pickett's Charge – a massive infantry assault across open fields against the center of the Union line – which failed with devastating losses. Lee's Army of Northern Virginia never fully recovered. The day after Gettysburg, Vicksburg surrendered to Grant, giving the Union control of the Mississippi River. Lee surrendered to Grant nearly two years later, on April 9, 1865, at Appomattox Court House. Grant offered generous terms: Confederate soldiers could return home with their horses and mules.

The 13th Amendment abolished slavery! Congress passed it on January 31, 1865, and it was ratified by the states on December 6, 1865. The amendment reads: "Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction." Over 4 million enslaved people were freed. The 14th Amendment (1868) granted citizenship to all persons born or naturalized in the United States, including formerly enslaved people. The 15th Amendment (1870) granted Black men the right to vote. These Reconstruction amendments were intended to secure equal rights, but enforcement was weak in the South.

Abraham Lincoln delivered the Gettysburg Address! The main speaker that day was Edward Everett, a famous orator, who spoke for two hours. Lincoln's two-minute speech was initially overlooked but later recognized as a masterpiece. The speech begins with "Four score and seven years ago" (87 years, referring to 1776) and ends with the famous call to ensure that "government of the people, by the people, for the people, shall not perish from the earth." Five known manuscript copies of the address survive. The speech is inscribed on the Lincoln Memorial in Washington, D.C., and remains a touchstone of American ideals.

The March to the Sea was Sherman's campaign from Atlanta to Savannah! Sherman famously cut his supply lines and ordered his army to live off the land. They destroyed railroads by heating the rails and wrapping them around trees (called "Sherman's neckties"), burned cotton gins and warehouses, and confiscated food and livestock. Sherman presented the city of Savannah to President Lincoln as a Christmas gift in December 1864. He then marched north through the Carolinas. Sherman's tactics were controversial – Southerners saw them as brutal; Northerners saw them as necessary to end the war quickly. Sherman later became General-in-Chief of the Army.

General Winfield Scott proposed the Anaconda Plan! Scott was a hero of the Mexican-American War. His plan called for three parts: (1) blockade Southern ports to cut off trade, (2) take control of the Mississippi River to split the Confederacy, and (3) capture Richmond, the Confederate capital. Critics mocked the plan as too slow, calling it the "Anaconda Plan" after the snake that suffocates its prey. But by 1864, the plan was working – Confederate ports were effectively closed, the Mississippi was under Union control (after Vicksburg), and Richmond fell in April 1865. The Monitor and Virginia battle demonstrated that wooden warships were obsolete – both ships survived the battle, and navies around the world shifted to ironclad construction.

Reconstruction was the post-Civil War period! It lasted from 1865 to 1877. President Andrew Johnson's lenient policies allowed Southern states to pass Black Codes, leading Congress (controlled by Radical Republicans) to take control of Reconstruction. The Freedmen's Bureau (1865-1872) provided food, housing, medical aid, schools, and legal assistance to freed slaves and poor whites. African Americans participated in Southern governments for the first time – hundreds were elected to state legislatures and over a dozen to Congress (including Hiram Revels and Blanche K. Bruce, the first Black U.S. senators). Reconstruction ended with the Compromise of 1877, which withdrew federal troops from the South. Without federal protection, Jim Crow laws and segregation were enforced for another 80 years, until the Civil Rights Movement of the 1950s-1960s.