Don Carlos Buell (March 23, 1818 – November 19, 1898) was a United States Army officer who fought in the Seminole War, the Mexican–American War, and the American Civil War. Buell led Union armies in two great Civil War battles—Shiloh and Perryville. The nation was angry at his failure to defeat the outnumbered Confederates after Perryville, or to secure East Tennessee. Historians generally concur that he was a brave and industrious master of logistics, but was too cautious and too rigid to meet the great challenges he faced in 1862. Buell was relieved of field command in late 1862 and made no more significant military contributions.