George Stoneman Jr. (August 8, 1822 – September 5, 1894) was a United States Army cavalry officer and politician who served as the fifteenth Governor of California from 1883 to 1887. He was trained at West Point, where his roommate was Stonewall Jackson, and graduated in 1846. Stoneman served in the Army for thirty-six years, though he was relieved of command in 1871. During this time, he was involved in multiple conflicts, including the Mexican–American War, though he did not see any combat, the Yuma War, and the American Civil War. In 1861, Stoneman was promoted to Brigadier General, and was later put in command of the Army of the Potomac's 3rd Infantry Corps, and subsequently the newly-created cavalry corps.