Born in Virginia, Thomas survived Nat Turner's rebellion as a boy, then studied at West Point, where Sherman was a classmate. Thomas distinguished himself in the Mexican War and then returned to West Point as an instructor. When the Civil War broke out, Thomas remained loyal to the Union, unlike fellow Virginia-born officer Robert E. Lee (among others). He compiled an outstanding record as an officer in battles at Mill Springs, Perryville, and Stones River. At the Battle of Chickamauga, Thomas, at the time a corps commander, held the center of the Union line under a ferocious assault, then rallied the troops on Horseshoe Ridge to prevent a Confederate rout of the Union army. His extraordinary performance there earned him the nickname "The Rock of Chickamauga."Promoted to command of the Army of the Cumberland, he led his army in a stunning Union victory at the Battle of Chattanooga. Thomas supported Sherman on his march through Georgia in the spring of 1864, winning an important victory at the Battle of Peachtree Creek. As Sherman continued on his March to the Sea, Thomas returned to Tennessee and in the battle of Nashville destroyed the army of Confederate general John Bell Hood. It was one of the most decisive victories of the war, and Thomas won it even as Grant was on his way to remove Thomas from his command.