Simplify the following text for a Grade 13 native English-speaking person.
Original: Ulysses S. Grant ( born Hiram Ulysses Grant ; April 27 , 1822 â `` July 23 , 1885 ) was the 18th President of the United States ( 1869 â `` 1877 ) as well as military commander during the Civil War and post-war Reconstruction periods .
Simplified: Ulysses S. Grant ( April 27 , 1822 - July 23 , 1885 ) , born Hiram Ulysses Grant , was the general whom many think won the American Civil War and later became the 18th President of the United States ( 1869-1877 ) .