Assaults by Confederate Lt. Gen. James Longstreet failed to break through the defensive lines of Union Maj. Gen. Ambrose Burnside, resulting in lopsided casualties, and the Siege of Knoxville entered its final days.

Union engineers commanded by Captain Orlando M. Poe built several fortifications in the form of bastioned earthworks near Knoxville.

[5] As a Confederate army under General Braxton Bragg besieged Union forces at Chattanooga, Tennessee, a detachment under the command of Lt. Gen. James Longstreet, a trusted subordinate of Robert E. Lee, was sent to Knoxville to prevent Burnside's Army of the Ohio from moving in support of Chattanooga.

[9] The Confederates moved to within 120-150 yards of the salient during the night of freezing rain and snow and waited for the order to attack.

Union soldiers rained fire into the assault, including musketry, canister, and artillery shells thrown as hand grenades.

[2] Longstreet undertook his Knoxville expedition, which he came to realize was far too soon, to divert Union troops from Chattanooga and to get away from General Braxton Bragg, with whom he was engaged in a bitter feud.

From the beginning of the artillery bombardment until the Confederates broke and retreated, the attack on Fort Sanders lasted about forty minutes.

In the brief period of 20 minutes of attacking, General Burnside's chief engineer, Orlando M. Poe, wrote that he was unaware in the annals of military history where a storming party was so nearly annihilated.

Lieutenant Benjamin reported the Union losses in the fort as five killed and eight wounded, significantly less than their defeated opponent.

The Union details pulled the dead out on blankets and carried them to a point halfway across no-man's-land for delivery to the Confederates.

On the afternoon of November 29, Longstreet changed his mind about disengaging from the Federals at Knoxville when dispatches arrived from Joseph Wheeler.

The cavalry general had reached Ringgold, Georgia, on November 25 while making his way back to the Army of Tennessee, only to find that Bragg had been severely beaten at Chattanooga.

Bragg asked him to inform Longstreet of the defeat and let him know to rejoin the Army of Tennessee at Dalton or to go back to Virginia if that was not possible.

This Confederate defeat, plus the loss of the Battle of Chattanooga on November 25, put much of East Tennessee in the Union camp.