After Abraham Lincoln won the presidential election, southern states began declaring their secession from the country. The Civil War began in April 1861 when Fort Sumter was attacked by the Confederate army. Four years of battles and conflict between the Union and Confederate armies followed. With more than 620,000 dead soldiers, the Civil War is the deadliest in U.S. history. There were 1,523 Medal of Honor recipients in the Civil War.
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