Howl.

Billy Yank, Sherman's Necktie, 1864

This month in 1864, General William Tecumseh Sherman "made Georgia howl", beginning his famous "March to the Sea".  In just over a month he moved his army from Atlanta to Savannah, Georgia, destroying property and routing small militia along the way. 

From This Day in Military History ...

He divided his force into two columns and widened the swath of destruction. The Yankees cut away from their supply lines at Atlanta and generally lived off the land. What they did not consume, they destroyed. More than 13,000 cattle fell into Union hands, as well as 90,000 bales of cotton and numerous sawmills, foundries, cotton gins, and warehouses. Sherman’s superiors, President Lincoln and General in Chief Ulysses S. Grant, endorsed his controversial tactic. Sherman argued that, although it would be brutal, destroying the resources of the South could bring the war to a speedy end.  The Union troops moved nearly unopposed across the region until they reached Savannah on December 21. The March to the Sea devastated Southern morale and earned Sherman the lasting hatred of many Southerners.

David McCullogh explains in Ken Burns' Civil War.