On this day in 1862, the Union Army of the Potomac occupies Fredericksburg, Virginia, as General Ambrose Burnside continues to execute his plan to capture the Confederate capital at Richmond, Virginia. However, the occupation did not happen until three weeks after Burnside's army had arrived at Falmouth, Virginia, just across the river from Fredericksburg. Due to a logistical error, pontoon bridges had not been available so the army could not cross; the delay allowed Confederate General Robert E. Lee ample time to post his Army of Northern Virginia along Marye's Heights above Fredericksburg.
Burnside replaced General George McClellan as head of the Army of the Potomac in early November 1862. He devised a plan to move his army quickly down the Rappahannock River, cross the river, and race Lee's army south to Richmond. Everything went according to plan as the Yankees sped south from Warrenton, Virginia. Burnside surprised Lee with his swiftness--the leading Union corps covered 40 miles in two days. The entire army was at Falmouth by November 19. Although ready to cross the Rappahannock, the army did not begin receiving the pontoon bridges until the end of the month due to mistakes made by the engineering corps. The delay allowed Lee to move his troops into position on the opposite side of the river. President Abraham Lincoln visited his army at the end of November, and, realizing that the element of surprise was lost, characterized Burnside's plan as "somewhat risky."
On December 11, Burnside's engineers finally began to assemble the bridges. Confederate snipers in Fredericksburg picked away at the builders, so Yankee artillery began a barrage that reduced to rubble many of the buildings along the river. Three regiments ran the sharpshooters out of the town, and the bridge was completed soon after. By evening on the 11th, the Union army was crossing the Rappahannock. By the next day, the entire army was on the other side and Burnside planned the actual attack.
The Battle of Fredericksburg, which took place on December 13, was an enormous defeat for the Army of the Potomac. Lee lost less than 5,000 men while Burnside lost some 12,600.