When the American Civil War started, Davis donated $50,000 to the Confederate States and raised the 1st Florida Cavalry Regiment for the Confederate States Army. He was elected colonel and given command of the Confederate provisional forces in eastern Florida. On March 25, 1862, he was sent to join General Albert Sidney Johnston in Tennessee.Boatner, Mark Mayo, III. The Civil War Dictionary. New York: McKay, 1988. . First published New York, McKay, 1959. p. 227 There, he commanded the 2d brigade in the 2d division (Heth's) from about July 3, 1862, to October 31, 1862, then the 1st brigade of the 3rd division (Heth's) of the Department of East Tennessee until December 1862. During the later period, on November 6, 1862, he was promoted to brigadier general. He commanded the 1st brigade of the District, Department of East Tennessee from December 1862 to early 1863. He then served as commander of the Department of East Tennessee until he resigned his commission on May 6, 1863.
