Granbury and his regiment served in north Mississippi with General Joseph E. Johnston’s Army of Tennessee during the Vicksburg Campaign. Colonel Granbury led the regiment in the battles of Raymond and Jackson. Granbury fought and was wounded at the Battle of Chickamauga. He then participated in the Siege of Chattanooga and the Battle of Missionary Ridge. When Brigadier General James Argyle Smith was wounded at Chattanooga, Granbury led the brigade in the retreat from Chattanooga. Division commander, Major General Patrick R. Cleburne, commended Colonel Granbury for his handling of the brigade.