It was not unusual for a militia officer from the South to wear a U.S. Army issue uniform dating from before the nation was divided by the Civil War.

Get a quick and clear explanation of the American Civil War in just one minute! Learn about the key events, causes, and ...

Civil War photos came courtesy of cinematographer Rob Hardy, who chose cameras that pull Dunst and Spaeny's photojournalists into combat.

In Legacy of Lies, El Salvador 1981-1984, photojournalist Robert Nickelsberg documents how U.S. foreign policy fueled a violent 13-year civil war in El Salvador.

Museum officials said, even 150 years later, it remains important to return the photos to families who had a link to the Civil War. The two girls, they said, still evoke powerful emotions.