The American Civil War was the first major conflict that was photographed extensively, bringing shocking and often horrific images to the front pages and into people's living rooms. Photography was extremely popular in the US at the time, and many photographers did not hold back from snapping even the most graphic of post-battle images to illustrate the horrors of war. Original captions were often scrawled below or on the backs of photos - you can read a few here in quotes.
Several of the images in this gallery are graphic in nature and may be disturbing.
The story of the American civil rights movement is told through its powerful music -- the freedom songs that protesters sang on picket lines, in mass meetings, in police wagons, and in jail cells as they fought for justice and equality.
Harry Truman was responsible for finding America's place at the start of the Cold War. Part of the award-winning Presidents collection.
The international race to develop biological weapons during the 20th century.
John Scopes' free speech trial pitted science against religion after the teacher presented Charles Darwin's theory of evolution in a Tennessee school.
In the summer of 1940, 10,000 children were sent from wartime Britain to the United States.
A great playwright's turbulent story, from childhood through the years of his Nobel Prize-winning career to his lonely, painful death.
After notorious revolutionary leader Pancho Villa's raid on Columbus, New Mexico, General John Pershing and his 150,000 man cavalry set out to get Villa.
Intrepid journalist Nelly Bly went on a journey around the world breaking the record of Julius Verne's fictional character.