Historians have often marginalized the effect of African American troops on the outcome of the Civil War. While many histories briefly mention the service of the blacks, few reveal their impact. Lorenzo Thomas was one of the most exceptional people to serve in that war, but no biography of his life has been written. Most of his career was spent as an administrator in the U. S. Army, from his graduation from West Point in 1823 until the start of the war when he was the army's Adjutant General. His life changed when he was charged by Secretary of War Stanton to go West and recruit troops for the Union that were desperately needed. Stanton and Thomas did not get along and with pressure mounting to get more troops, Stanton saw this as an opportunity to get Thomas out of Washington. Thomas did exceptionally well in recruiting tens of thousands of troops for the Union. After the war ended, President Andrew Johnson replaced Stanton with Thomas as temporary Secretary of War. This precipitated the impeachment hearings against Johnson and some say that the testimony of Thomas caused the impeachment of Johnson to be dismissed.