Kentucky and Tennessee share a unique and similar history, having joined the Union as the fifteenth and sixteenth states in 1792 and 1796, respectively. During the antebellum period, Kentuckians and Tennesseans enjoyed a common culture, pursued a largely agricultural way of life, and shared many values, particularly a deep-seated commitment to slavery. However, the people of these two sister states found themselves on opposing sides at the most critical time in American history, as Tennessee sided with the Southern states seceding from the Union, and Kentucky, after a brief period of neutrality, remained loyal to the Union. Each state assumed enormous importance to both the Union and the Confederacy, for whichever side controlled them commanded vast quantities of resources desperately needed by the South. Perhaps most important, control of this strategic region would determine where much of the fighting in the West would take place, either on northern soil or farther south. Both states felt the hard hand of war as the conflict visited them early and often, and Kentuckians and Tennesseans suffered the same hardships while war was waged within their borders. Surprisingly, the Civil War in the Volunteer and Bluegrass states has not garnered the attention by scholars that it deserves, and few works have dealt exclusively with both of these states. In Border Wars, prominent Civil War historians Benjamin Franklin Cooling, Stephen D. Engle, Earl J. Hess, Jack Hurst, and Wiley Sword, along with other distinguished scholars, explore the military contests in this vital region. There were several wars taking place simultaneously along the border of Kentucky and Tennessee. There was, of course, the war between the Union and the Confederacy, but there was also fighting between the Union occupiers and the pro-Southern civilians they encountered. Hostilities even existed between the Federal army and local Unionists in some areas, and there was conflict among some Union generals and among Confederate commanders in the region. With its unique exploration of these wars and conflicts and the individuals involved, Border Wars adds an important chapter to our nation’s history.