April 12, 2011 -- The popular use of photography during the Civil War led to the creation of an unprecedented archive of one of the most critical times in American history.
Explore some of the lesser-known faces of the Civil War, from the children of soldiers to the African Americans who fought for their own freedom, in this slide show.
The African American Soldier
These photos show two unidentified African American soldiers in uniform.
According to the National Archives, approximately 10 percent of the Union Army was black: nearly 179,000 soldiers.
The Families Left Behind
An unidentified girl in mourning dress holds a photograph of her father. The Hardee hat, sword and uniform identify the man as a cavalry soldier.
More than 600,000 soldiers died in the Civil War, many from a lack of sanitary facilities, as modern medicine was still in its earliest stages.
A Soldier's Family
This photo from the Library of Congress shows an unidentified African-American Union soldier with his wife and two daughters.
Initially, black soldiers enlisted in the Union Army were paid less than white soldiers and often were treated worse when captured, if not killed outright, according to the National Archives.
In 1863, the Lincoln administration issued this decree promising black soldiers equal pay and equal protections.
Native Americans played an interesting part in the American Civil War, oftentimes on the side of the Confederacy because of treaties signed at the beginning of the war, according to the Indiana Department of Education.
About 3,600 Native Americans also served for the Union Army.
The photo above shows Civil War veteran Joe Tasson.
Humor in a Time of Horror
Two unidentified Union soldiers pose for a photograph holding cigars in each others' mouths.
More photographs of Union soldiers exist than of Confederate soldiers, according to the Library of Congress. The North had more photographers and supplies during the war.