Notes

 The American Civil War, widely known in the United States as simply the Civil War as well as other sectional names, was a civil war fought from 1861 to 1865 to determine the survival of the Union or independence for the Confederacy. Among the 34 states in January 1861, seven Southern slave states individually declared their secession from the United States and formed the Confederate States of America. The Confederacy, often simply called the South, grew to include eleven states, and although they claimed thirteen states and additional western territories, the Confederacy was never diplomatically recognized by a foreign country. The states that remained loyal and did not declare secession were known as the Union or the North. The war had its origin in the fractious issue of slavery, especially the extension of slavery into the western territories. After four years of combat, which left over 600,000 Union and Confederate soldiers dead and destroyed much of the South's infrastructure, the Confederacy collapsed and slavery was abolished. Then began the Reconstruction and the processes of restoring national unity and guaranteeing civil rights to the freed slaves.
In the 1860 presidential election, Republicans, led by Abraham Lincoln, opposed the expansion of slavery into U.S. territories. The Republican Party, dominant in the North, secured a majority of the electoral votes, and Lincoln was elected the first Republican president, but before his inauguration on March 4, 1861, seven slave states with cotton-based economies formed the Confederacy. The first six to secede had the highest proportions of slaves in their populations, a total of 48.8% for the six. Outgoing Democratic President James Buchanan and the incoming Republicans rejected secession as illegal. Lincoln's inaugural address declared his administration would not initiate civil war. Eight remaining slave states continued to reject calls for secession. Confederate forces seized numerous federal forts within territory claimed by the Confederacy. A peace conference failed to find a compromise, and both sides prepared for war. The Confederates assumed that European countries were so dependent on "King Cotton" that they would intervene; none did and none recognized the new Confederate States of America.
Hostilities began on April 12, 1861, when Confederate forces fired upon Fort Sumter, a key fort held by Union troops in South Carolina. Lincoln called for every state to provide troops to retake the fort; consequently, four more slave states joined the Confederacy, bringing their total to eleven. The first bloodshed of the Civil War occurred in Maryland during the Baltimore riot of 1861 on April 19. Lincoln soon controlled the border states, after arresting state legislators and suspending habeas corpus, ignoring the ruling of the Supreme Court's Chief Justice that such suspension was unconstitutional, and established a naval blockade that crippled the southern economy. The Eastern Theater was inconclusive in 1861–62. The autumn 1862 Confederate campaign into Maryland ended with Confederate retreat at the Battle of Antietam, dissuading British intervention. Lincoln issued the Emancipation Proclamation, which made ending slavery a war goal.
Causes of secession
The causes of the Civil War were complex and have been controversial since the war began. James C. Bradford wrote that the issue has been further complicated by historical revisionists, who have tried to offer a variety of reasons for the war. Slavery was the central source of escalating political tension in the 1850s. The Republican Party was determined to prevent any spread of slavery, and many Southern leaders had threatened secession if the Republican candidate, Lincoln, won the 1860 election. After Lincoln had won without carrying a single Southern state, many Southern whites felt that disunion had become their only option, because they thought that they were losing representation, which would hamper their ability to promote pro-slavery acts and policies.