The reorganized 1st Wisconsin was ordered to proceed to Jefferson, Indiana, and then to Elizabethtown, Kentucky, where they were attached to the brigade of General James S. Negley, in the division of Alexander McDowell McCook, and shortly thereafter became part of the Army of the Cumberland. With his regiment, Timme participated in the battles of Perryville, Stones River, Hoover's Gap, and Chickamauga, in the campaign for control over Middle Tennessee in the western theater of the war. Timme was wounded during the first day of fighting at the Battle of Chickamauga; the wound was so severe that the surgeon had to amputate his left arm. Though only a private at the time, for his bravery at Chickamauga, he received a brevet to the rank of captain, and later advanced to colonel.