1862
Battle of Shiloh (Pittsburg Landing)
The setting
Hardin County, Tennessee, United States
Wooded plateau near the Tennessee River, with ravines and a sunken road ("Hornet's Nest")
Reveal the outcome
Recorded sideConfederate States
Recorded resultdefeat
Union victory; Confederate assault stalled and was driven back on the second day
How the atlas explains it
A surprise Confederate assault nearly overran Grant's army on April 6, but a stubborn Union defense (the Hornet's Nest) bought time; the overnight arrival of Buell's Army of the Ohio gave Grant the numbers to counterattack and recover the field on April 7.
What followed
Shocked both nations with its unprecedented bloodshed and demonstrated the war's scale; secured Union momentum in the Western Theater and the loss of Confederate commander Albert Sidney Johnston.