The Mud March was Union Major General Ambrose Burnside’s second attempt to advance his Army of the Potomac across the Confederate defenses along the Rappahannock River and advance to capture the Confederate capital at Richmond.

Background

Burnside’s first attempt had failed in mid-December. A series of disastrous frontal attacks were launched against strong Confederate entrenchments along the bluffs behind the river at Fredericksburg. Wave after wave of men charged the defences, but not a single man reached the Confederate works. The casualty list for the day was almost 13,000 men, more than twice the losses inflicted on Lee’s army.

Officers and enlisted men lost confidence in Burnside. Desertions and resignations reached record levels. Burnside was under extreme pressure to do something quickly to put the disaster at Fredericksburg behind him.

Initial Plan

Burnside’s first plan involved crossing the Rappahannock seven miles downstream from Fredericksburg where there were no high bluffs on the Confederate side of the river. Feints would be carried out upstream to divert Confederate attention. A large cavalry raid would send 1,500 troopers 20 miles upstream. One group of around 500 would move toward Culpeper before returning to the Falmouth area. The main group would make an audacious ride curving around the West and south side of Richmond before reaching Federal lines at Suffolk. They would then return to Falmouth by ship.

The cavalry started its movement after the the first of the year and were about to cross the Rappahannock at Kelly’s Ford when orders were received from Washington that “No major army movements are to be made without first informing the White House.” Everything came to a stop.

Betrayal and Dissention

Burnside was astonished. The plan had been kept secret. Even most of the officers of the army were not aware of it. He headed to Washington to find out what had happened. Burnside met with Lincoln to find that two officers – who Lincoln refused to reveal – had met with Lincoln. They had told him that after the Fredericksburg debacle the Army of the Potomac would fall apart if it were sent into another campaign.

An angry Burnside responded that the two anonymous officers should be court martialled. He went on to denounce both Secretary of War Edwin M. Stanton and General in Chief Henry Halleck, arguing that “it would be for the good of the nation if both were replaced.” Before leaving he told Lincoln that the way things were going, he might as well resign both command of the Army of the Potomac and his commission and leave the military entirely.

Lincoln met with Halleck after Burside left. He suggested that Halleck should go down to Fredericksburg and provide direction. But Halleck had nothing meaningful to contribute. The last thing he wanted was to risk his reputation in the mess that the Army of the Potomac had become.

Lincoln reluctantly told Burnside to reconsider resigning from the army. Burnside had been chosen by Lincoln to replace George McClellan in November, and removing him so quickly afterward would reflect poorly on the administration Plus there was the problem of who would replace him.

The Second Plan

Burnside revised his plan. He dropped the idea of the cavalry raid. Instead of crossing the Rappahannock downstream he would cross upstream at U.S. Ford, about eight miles march from Falmouth. Here there were no bluffs on the other side for Confederate defensive positions, and the Army of the Potomac could make use of its superior numbers.

The movement began on January 20 during an unseasonably mild warm spell. Burnside decided to make his crossing even closer, at Banks’ Ford, cutting three miles off the army’s march. At first light on the 21st five pontoon bridges would be thrown across the river. Four corps would cross there, while another two corps would provide a diversion by repeating the crossing at Fredricksburg.

Disaster

But on the evening of the 20th heavy rains began to fall and kept up all night. By dawn the ground was soaked. The already miserable Virginia roads were a swamp, churned by the wheels of the heavy pontoon trains and the artillery. One bridge was almost ready but the approaches to the river were almost impassable, with tales of guns and mules sinking almost out of sight. Meanwhile a huge jam of tens of thousands of cold, soaked men huddled in the deep mud all the way back to the camps in Falmouth.

Lee took advantage of the delay to move some of his forces to cover the crossing. But except for sharpshooters picking off the engineers he did not interfere. Indeed, he wanted Burnside to try to cross, where part of his army could be trapped on the far side of a rising river. But even stubborn Burnside could see that the campaign was a failure. He gave the order to abandon the crossing and return to camp. What became known as the Mud March was over.

It was a good plan – Hooker would follow much of it for his Chancellorsville Campaign – but it was bad luck. And no one likes an unlucky general Burnside was relieved of command and replaced with Major General Joseph Hooker five days later.