Of the 2,213,363 men who served in the Union Army during the Civil War, 364,511 died in combat, or from injuries sustained in combat, disease, or other causes, and 281,881 were wounded. More than 1 out of every 4 Union soldiers was killed or wounded during the war; casualties in the Confederate Army were even worse—1 in 3 Southern soldiers were killed or wounded. It should be noted, however, that the Confederates suffered a considerably lower amount of overall casualties than the Union, at roughly 260,000 total casualties to the Union's 360,000. This is by far the highest casualty ratio of any war in which America has been involved. By comparison, 1 out of every 16 American soldiers was killed or wounded in World War II, and 1 out of every 22 during the Vietnam War.
In total, 620,000 soldiers died during the Civil War. There were 34 million Americans at that time, so 2% of the American population died in the war. In today's terms, this would be the equivalent of 5.9 million American men being killed in a war.
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