A Confederate success during their invasion of Kentucky in the autumn of 1862. Munfordville was defended by a Union force of 4,000 men, perfectly large enough to deal with any Confederate raiders, but far too small to resist the army of 30,000 men that was heading towards it at the start of September 1862.
That army had been led north from Chattanooga by General Braxton Bragg. He was hoping that the presence of a Confederate army in the state would encourage the state to join the Confederacy, in the process undoing the damage done to the Confederate cause in that state done earlier in the year by General U.S. Grant.
By the middle of September, Bragg was engaged in something of a race north against a Union army under General Buell. Until now, the Union army had remained significantly further west, unsure exactly where Bragg was headed, but by now it was clear that he was heading north. Both armies began to head towards Munfordville.
The Confederates got there first. On 13 September a cavalry brigade had reached the town, and unaware that they were outnumbered had demanded the surrender of the garrison. The next day General Chalmers arrived, bringing the Confederate forces around the town up to 1,913. Still unaware of the real size of the Union garrison, Chalmers now attacked the town, suffering a serious repulse (35 killed and 253 wounded, of 15% of his total force).
The two main armies were now getting closer. On 14 September Buell’s army was at Bowling Green, thirty miles to the south west. Bragg was at Glasgow, fifteen miles south. Bragg moved first. Learning of Chalmer’s repulse, on 15 September the Confederate army marched north. Buell did not leave Bowling Green until the following day. That same day, the Confederate army reached Munfordville. The garrison now had no choice. On 17 September a force of 4,076 Union soldiers surrendered.
The aftermath saw first Bragg and then Buell prepared to risk a full scale battle around Munfordville. On 16 September Buell had marched towards Glasgow, before turning north towards Munfordville. He arrived there late on 17 September, too late to save the garrison. The two armies now spent four days facing each other, just waiting for the right moment to fight. For the first three days (17-19 September), Buell had about 35,000 men present at Munfordville, Bragg close to 30,000. If Buell had attacked during those three days, Bragg would have stood and fought. However, on 20 September General Thomas joined Buell. Buell was now willing to fight, but Bragg decided to withdraw. The first chance for a decisive battle in Kentucky slipped away. After Munfordville, Buell decided to head for his base at Louisville, due north, while Bragg heading north east towards the state capitol at Frankfort, and a union with Kirby Smith’s army.