In late July, 1864, as Maj. Gen. Jubal Early withdrew south after the battle at Cool Spring, the Union command believed he was returning to Robert E. Lee’s army outside of Petersburg. Accordingly, the Union VI and XIX Corps were sent back to the Army of the Potomac, leaving. Brig. Gen. George Crook with three divisions and some cavalry to hold Winchester. Mindful of Lee's orders to prevent Union reinforcements from being sent east, Early marched north again on July 24 against Crook at Kernstown. After an hour of stubborn resistance at Pritchard’s Hill, the Federal line collapsed and Crook’s divisions streamed back in disarray through the streets of the town. Crook retreated all the way back to the Potomac River. Emboldened after his victory, Early carried the war north and burned Chambersburg, Pennsylvania on July 30.