Ulysses S. Grant was a successful military general and the eighteenth President of the United States. A graduate of the prestigious West Point military academy, Grant served in both the Mexican-American War (1846-1848) and the American Civil War (1861-1865), in which he was appointed commander of the Union Army. Grant's successful military campaign against the Confederate States, executed by Union Generals William Tecumseh Sherman, Philip Sheridan, and George Thomas, culminated in his acceptance of General Robert E. Lee's surrender at Appomattox courthouse on April 9, 1865.