Battle of Mill Springs/Fishing Creek
The Battle of Mill Springs, Ky was the first major Union Victory of the Civil War and the first of twelve campaigns for the Army of the Cumberlands. It was part of the struggle for the control of Cumberland Gap on the far right of the Confederate western theater which stretched from eastern Kentucky to Columbus, Ky. on the Mississippi River. Cumberland Gap was the main pass in the Cumberland Mountains between East Tennessee (rich in salt and essential metals for weapons production) and Kentucky. East Tennessee was also largely in favor of remaining in the Union, and Confederate President Jefferson Davis was determined to prevent it from seceding from the Confederacy. The outcome of this contest would determine the outcome of the Civil War.

With Union forces of 4000 men under the leadership of General George Thomas against a Confederates force of about an equal number led by General George Crittenden, the CSA decided to take the initiative before the opponents could concentrate resources, and attacked early in the morning on 19 Jan 1862 in a driving rain, hoping the benefit of surprise would provide them with the advantage. However, General Thomas anticipated such and with several lines of pickets their action were communicated it was impossible to surprise the union forces. It also did not help that Crittenden's men were mostly ill equipped with primitive muskets whose ability to fire suffered greatly under those harsh winter conditions. It turned into a confused push and shove contest between scattered units. Early in the engagement General Felix Zollicoffer, CSA lost his bearings and approached the Union position. He was wearing a white raincoat and thus made an easy target, and was shot down. Some of Zollicoffer's units began to retreat, but Crittenden was able to reestablish control. While keeping Crittenden engaged in the center, Thomas ordered a counter-attack against the Crittenden's left and crushed it. This in turn broke the entire Confederate line which fell back in disorder to the Cumberland and crossed over to the south bank that evening, leaving behind most of the heavy equipment.

The effect of this battle was to start unraveling the confederate defensive line in Kentucky. Fort Donelson, the next key position to the west of Cumberland Gap, was thus outflanked, and its defense became untenable. The stakes were high for General Thomas, no victory at Mill Springs, no victory at Ft. Donelson.