The battle on November 3 was intended to be a Confederate cavalry raid to break up the Memphis & Charleston Railroad behind Maj. Gen. William T. Sherman's XV Army Corps, then in the process of marching to the relief of Chattanooga. But, when Confederate Brig. Gen. James R. Chalmers, leading a cavalry division riding up from Mississippi, learned that only one Union regiment was left to defend Collierville, he decided to attack. Chalmers supposed Union Col. Edward Hatch possessed fewer men stationed at Collierville and at Germantown, five miles (8 km) to the west, than he actually did. Hatch's scouts warned him of Chalmers's approach from the south, so he ordered Collierville's defenders to be prepared and rode from Germantown with cavalry reinforcements.