Ulysses S. Grant (born Hiram Ulysses Grant; April 27, 1822 – July 23, 1885) was an American soldier and politician who served as the 18th president of the United States from 1869 to 1877. After Grant's victory at Chattanooga, President Abraham Lincoln promoted Grant to Lieutenant General. For thirteen months, Grant fought Robert E. Lee during the high casualty Overland Campaign and at Petersburg. During the Civil War, he joined the Union Army in 1861, and led the Vicksburg campaign, which gained control of the Mississippi River in 1863. After Grant's victory at Chattanooga, President Abraham Lincoln promoted Grant to Lieutenant General. For thirteen months, Grant fought Robert E. Lee during the high casualty Overland Campaign and at Petersburg.