Video: 'Civil War Combat: Massive Assault at the Battle Of Fredericksburg (S1, E2) | Full Episode' (Dec. 12-13, 1862, at 13:15)

(Saturday, December 13, 1862, 10:00 a.m. local time; during the American Civil War) — Maj. Gen. Ambrose Burnside suffered one of the most decisive losses for the Union Army during of the American Civil War when he hurled 14 attacks against the Confederate lines today at Marye Heights, above Fredericksburg, Virginia, during the Battle of Fredericksburg, fought in the Eastern Theater of the American Civil War.

Video: 'Fredericksburg: Animated Battle Map' (Dec. 13, 1862, at 7:59)

Although the Union artillery was effective, the rebels were secure in a sunken road protected by a stone wall above a 600-yard field that became a killing ground for the attacking Yankees.

No Union soldiers reached the wall at the top of Marye’s Heights, and few even came within 50 yards of it.

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The Union army suffered 12,653 casualties while the Confederates counted 5,377.

It was during this battle that Confederate Gen. Robert E. Lee is said to have remarked: “It is well that war is so terrible, or we should grow too fond of it.”

On Dec. 15, 1862, Burnside withdrew his army, ending another failed Union campaign in the Eastern Theater.