Who was the President of the United States in 1857?

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United States: Andrew Johnson.

Following Abraham Lincoln's assassination on April 15, 1865, Vice President Andrew Johnson (born December 29, 1808 in Raleigh, North Carolina; died July 31, 1875 in Elizabethton, Tennessee) became the seventeenth President of the United States, serving from 1865 April 15 to 1869 March 4.