History: American Civil War (1861-1865)

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Slavery for the Confederacy's 3.5 million blacks effectively ended when Union armies arrived; they were nearly all freed by the Emancipation Proclamation. Slaves in the border states and those located in some former Confederate territory occupied prior to the Emancipation Proclamation were freed by state action or (on December 18, 1865) by the Thirteenth Amendment. The full restoration of the Union was the work of a highly contentious postwar era known as Reconstruction. The war produced about 1,030,000 casualties (3% of the population), including about 620,000 soldier deaths—two-thirds by disease. The war accounted for roughly as many American deaths as all American deaths in other U.S. wars combined.
The causes of the war, the reasons for its outcome, and even the name of the war itself are subjects of lingering contention today. Based on 1860 census figures, 8% of all white males aged 13 to 43 died in the war, including 6% in the North and 18% in the South. About 56,000 soldiers died in prisons during the Civil War. One reason for the high number of battle deaths during the war was the use of Napoleonic tactics, such as charging. With the advent of more accurate rifled barrels, Minié balls and (near the end of the war for the Union army) repeating firearms such as the Spencer repeating rifle, soldiers were mowed down when standing in lines in the open. This led to the adoption of trench warfare, a style of fighting that defined the better part of World War I.