posted by haley .
General Grant's army came closest to defeat in the West as a result of a surprise Confederate attack at the Battle of
The Battle of Shiloh, also known as the Battle of Pittsburg Landing, was a major battle in the Western Theater of the American Civil War, fought April 6–7, 1862, in southwestern Tennessee. A Union army under Maj. Gen. Ulysses S. Grant had moved via the Tennessee River deep into Tennessee and was encamped principally at Pittsburg Landing on the west bank of the river. Confederate forces under Generals Albert Sidney Johnston and P. G. T. Beauregard launched a surprise attack on Grant there. The Confederates achieved considerable success on the first day, but were ultimately defeated on the second day.
On the first day of the battle, the Confederates struck with the intention of driving the Union defenders away from the river and into the swamps of Owl Creek to the west, hoping to defeat Grant's Army of the Tennessee before the anticipated arrival of Maj. Gen. Don Carlos Buell's Army of the Ohio. The Confederate battle lines became confused during the fierce fighting, and Grant's men instead fell back to the northeast, in the direction of Pittsburg Landing. A position on a slightly sunken road, nicknamed the "Hornet's Nest", defended by the men of Brig. Gens. Benjamin M. Prentiss's and W. H. L. Wallace's divisions, provided critical time for the rest of the Union line to stabilize under the protection of numerous artillery batteries. Gen. Johnston was killed during the first day of fighting, and Beauregard, his second in command, decided against assaulting the final Union position that night.
Reinforcements from Gen. Buell and from Grant's own army arrived in the evening and turned the tide the next morning, when the Union commanders launched a counterattack along the entire line. The Confederates were forced to retreat from the bloodiest battle in United States history up to that time, ending their hopes that they could block the Union advance into northern Mississippi.
Got this info for wiki.