James Brown performs at KCOP Studios on the Lloyd Thaxton Show with Lloyd Thaxton in 1964. Brown helped popularize boogaloo-style dancing, shown here.
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Former Texas Rep. Beto O'Rourke (third from left) speaks as Sens. Cory Booker, Elizabeth Warren and Amy Klobuchar look on during the first night of the Democratic presidential debate, Wednesday in Miami.
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Civil rights activists are blocked by National Guardsmen brandishing bayonets while trying to stage a protest on Beale Street in Memphis, Tenn.
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Engraving shows the arrival of a Dutch slave ship with a group of African slaves for sale, Jamestown, Va., 1619.
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