The Battle of Fredericksburg, fought from December 11 to December 15, 1862, was a decisive Confederate victory that significantly boosted Southern morale.

Union forces, under General Ambrose Burnside, launched a series of ill-fated assaults against well-entrenched Confederate troops led by General Robert E. Lee. The battle showcased the effectiveness of Confederate defensive strategies and highlighted the challenges facing the Union Army. The heavy Union casualties, approximately 12,000 compared to around 5,000 for the Confederates, underscored the difficulties the North faced in achieving a quick victory, influencing military and political strategies in the ongoing war.