Museum displays include examples of robes worn by the men, women and children of the Ku Klux Klan. Bill Bitzinger/Ferris State University hide caption

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A disastrous rehearsal for D-Day took place on Slapton Sands in southwestern England. Terry Smith/Time & Life Pictures/Getty Image hide caption

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Three years ago, Rufus McDonald found historic documents in an abandoned house and took them to a rare-books dealer. The papers and books belonged to Richard T. Greener, a 19th century intellectual who was the first African-American to graduate from Harvard University. Cheryl Corley/NPR hide caption

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White Citizens' Council leader Asa Earl Carter denounces school integration in Clinton, Tenn., on Aug. 31, 1956. AP hide caption

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The Gospel, buried with St. Cuthbert in 698, was recovered from his grave in 1104. Its beautiful red leather binding is original. Courtesy of the British Library hide caption

itoggle caption Courtesy of the British Library

The flag covers the Green Monster as the national anthem is played before the game between the Boston Red Sox and the Tampa Bay Rays on April 16 at Fenway Park in Boston. Elsa/Getty Images hide caption

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The barons wanted King John to stop seizing their grain. The fish weirs had to go, too. Wikimedia Commons hide caption

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U.S. Navy crewmen watch a B-25 bomber take off from the USS Hornet for the Doolittle Raid on Tokyo on April 18, 1942. AP hide caption

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