Scottish explorer Mungo Park was among the first Europeans to view the Mandinka tribe's masked dancers who were known as Maamajomboo. He translated the word as "mumbo jumbo.' This 1797 illustration from Park's book, "Travels In The Interior Districts of Africa" shows a view of Kamalia village in Mandinka country. DeAgostini/Getty Images hide caption

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Ralph Ellison in 1957, four years after his novel Invisible Man won the National Book Award. Ellison died in 1994. James Whitmore/The Life Picture Collection/Getty Images hide caption

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A photograph of Parminder Singh Shergill is displayed during his funeral services at Cherokee Memorial Park in Lodi, Calif., on Feb. 8. Randall Benton/Sacramento Bee hide caption

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Since 1989, Rep. John Conyers, D-Mich., has introduced into each session of Congress a bill called HR 40, Commission to Study Reparation Proposals for African Americans Act. Carolyn Kaster/AP hide caption

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