March to Fredericksburg
‘Behind the Lines,’ by Donald C. Pfanz
Why Burnside chose to send the Army of the Potomac this way in 1862
Third in a series on the 1862 Battle of Fredericksburg
GEN. AMBROSE E. BURNSIDE felt as if the weight of the world rested on
his shoulders, and, in a manner of speaking, it did, for on Nov. 7, 1862,
President Abraham Lincoln had appointed the affable Indiana native to
command the Army of the Potomac.
At 115,000 men, the Army of the Potomac was, by far, the Union’s largest
body of men. For more than a year, it had been fighting Gen. Robert E.
Lee’s Confederates in Virginia and Maryland and rarely had it won. As
the army’s new commander, it was Burnside’s job to change that. The question
Burnside had accepted the command with the utmost reluctance, but once
in the job he moved with uncharacteristic energy. His first step was to
reorganize the army. At the time he took command, seven corps comprised
the Army of the Potomac. Burnside felt that this was too many for one
man to effectively wield in combat, and he promptly reorganized the army
into three “grand divisions” of two corps apiece. (One corps, the 11th,
remained unattached on duty in Northern Virginia.)
To command the grand divisions, Burnside selected his three highest-ranking
officers: William B. Franklin, Edwin Sumner and Joseph Hooker. Of the
three, only Hooker had shown any aptitude for high command. Franklin was
a protégé of McClellan’s and, like his mentor, was cautious and slow.
Sumner, by contrast, was a gallant old soldier of 65 winters, a former
dragoon who would charge hell itself if ordered to do so. At Fredericksburg,
he would do just that.
Opposing Burnside was a Confederate army of 78,000 men led by Lee. The
Southern army was dangerously divided. Half of it, under James Longstreet,
occupied Culpeper, blocking a direct advance by Burnside on Richmond.
The other half, led by Thomas J. “Stonewall” Jackson, lay across the Blue
Ridge in the Shenandoah Valley, looking for an opportunity to sweep through
the mountain passes onto Burnside’s vulnerable lines of supply.
Conventional military wisdom dictated that Burnside attack and overwhelm
Longstreet’s corps before Jackson could come to its assistance. That was
the plan of action McClellan would have taken-or at least so he later
claimed. But Burnside had other ideas.
Even if he defeated Longstreet, the Union commander reasoned, the Confederates
would simply retreat to a new line closer to Richmond. The closer Longstreet
got to Richmond, the stronger he would become. Burnside, by contrast,
would grow weaker as he advanced south because he would have to detail
troops to protect his growing line of supply.
It was that line of supply that troubled Burnside the most. To feed,
clothe, and supply his massive army, Burnside relied on the Orange &
Alexandria Railroad, which ran south from Alexandria to Gordonsville,
then south and east to Richmond. The railroad was barely able to supply
his army under the best of conditions. If Jackson, or Confederate cavalry,
managed to cut the railroad even for a few days, Burnside’s men and animals
would face the prospect of starvation.
Then there was Washington. As commander of the Army of the Potomac,
Burnside’s top priority was to protect the Union capital. Advancing down
the Orange & Alexandria Railroad, via Gordonsville, would pull Burnside
west, away from the capital, making it vulnerable to a quick Confederate
In light of these difficulties, the new commander determined to shift
his army to Fredericksburg, and advance toward Richmond by way of the
Richmond, Fredericksburg & Potomac Railroad. The Fredericksburg route
had much to recommend it. It would keep Burnside closer to the Union-controlled
rivers, thereby making it easier and safer to supply his army; it kept
him between Lee’s army and Washington, and it got him away from Jackson’s
In fact, there was only one drawback to the Fredericksburg route: the
Rappahannock River. At Culpeper, the Rappahannock is little more than
a stream, fordable at any number of spots. By the time it reaches Fredericksburg,
however, it broadens to a sizable river, 400 feet in width, making it
necessary to use bridges. And that was the problem, for there were no
bridges at Fredericksburg. The Confederates had destroyed them all earlier
in the war.
The solution was to employ pontoons, portable bridges that floated on
boats. The Army of the Potomac owned a pontoon train, but, unfortunately,
it had been left back at Berlin, Md., a few weeks earlier when the army
had crossed the Potomac River into Virginia. No matter; Burnside would
simply have officials in Washington order the pontoon train from Berlin
to Aquia Creek. From there, engineers could haul the pontoons overland
the remaining distance to Fredericksburg.
With that difficulty solved, Burnside submitted his plan to the president.
Lincoln at first was cool to the proposal. After all, he had put Burnside
in charge of the army to bring the Confederate army to battle. But now
that Burnside was command, he intended to march away from the enemy and
go to Fredericksburg.
Lincoln sent two emissaries to Burnside’s headquarters near Warrenton,
to discuss the matter. In the end, Burnside got his way. “The President
has just assented to your plan,” Gen.-in-Chief Henry Halleck wired from
Washington on Nov. 14. “He thinks that it will succeed if you move rapidly;
Rapid movement was not Burnside’s strength. Like McClellan before him,
he had what contemporary wags referred to as “the slows.” But, in this
instance, the general disappointed his critics by moving with unusual
Gen. Edwin Sumner’s Right Grand Division led the march. Breaking camp
on Nov.15, the old dragoon reached Falmouth in just two days’ time. Across
the Rappahannock River lay Fredericksburg, defended by a force of less
than 1,000 men.
While Northern guns threw shells into the town from a point near modern-day
Falmouth Baptist Church, occupying the Southerners’ attention, Sumner
ordered the Irish Brigade to splash across the river at Falmouth and seize
The brigade was halfway across when Burnside arrived. Fearful that the
river might rise and cut his army in two, Burnside ordered Sumner to recall
his troops to the north bank. He would await the arrival of the pontoons.
NEXT: The Case of the Missing Pontoons
DONALD C. PFANZ is staff historian at Fredericksburg and Spotsylvania
National Military Park. He is author of “Abraham Lincoln at City Point”
and “Richard S. Ewell: A Soldier’s Life.”