In eastern Kentucky, Union forces defeat Confederate troops at Mill Spring

Civil War Battle, iconic image
Union General George H. Thomas marched on the Confederate forces guarding the Cumberland Gap in eastern Kentucky.  Attempting to strike before the federal strength was consolidated, Confederate troops under General George B. Crittenden attacked Thomas and his men at Logan's Crossroad's in the early hours of the morning.  Fighting raged all day, during which Confederate General Felix Zollicoffer was killed, till Union units forced the Confederates to retreat, winning a small but morale-boosting Northern victory.  (By John Osborne)  
Source Citation
 
Chronicles of the Great Rebellion Against the United States of America (Philadelphia, PA: A. Winch, 1867), 18.