1863
Battle of Chancellorsville
The setting
Spotsylvania County, Virginia, United States
Dense second-growth woodland ("the Wilderness") with limited roads and clearings
Reveal the outcome
Recorded sideUnited States (Union)
Recorded resultdefeat
Confederate victory; Hooker's larger army was outmaneuvered and withdrew across the Rappahannock
How the atlas explains it
Facing a force more than twice his size, Lee violated military convention by dividing his outnumbered army, sending Jackson on a concealed 12-mile flank march through the Wilderness to crush the exposed Union right flank in a surprise evening assault that collapsed Hooker's line.
What followed
Often called Lee's greatest tactical masterpiece, achieved against long odds. The victory came at a devastating cost: Stonewall Jackson's mortal wounding removed Lee's most capable corps commander just before the Gettysburg Campaign.