On November 15, 1862. Burnside wanted to move quickly in order to avoid the type of criticism that had previously gone to McClellan. Burnside had a good plan, which was to cross the Rappahannock River at Fredericksburg and move quickly against Richmond. Lee and the Army of Northern Virginia would be forced to throw themselves in his way, and he would fight them at an advantage.

The trouble lay in execution of the plan. The roads were full of mud, and the heavily laden Army of the Potomac moved more slowly than anticipated. Even so, Burnside did get to the Rappahannock in time to make a quick move across, but the pontoon bridges were not ready. While he waited, the Army of Northern Virginia began to coalesce.