From "The Rebel's Yell," Courtesy of The Library of Congress, Motion Picture, Broadcasting and Recorded Sound Division

Ever since the Civil War ended, writers have struggled to adequately describe the Rebel Yell.

For the first time at Manassas or Bull Run in 1861, and then at many battlefields afterward, the bluecoats heard the unearthly wail of the rebel yell.

“When we got in sight of the Yankees,” Thomas D. Wallace, a member of the 13th Mississippi Infantry and a comrade of Francis M. Poore, recorded in his diary, “we raised a yell that Indians could not have raised.”

At Gettysburg in 1863, as 1,400 Mississippians stepped toward Emmitsburg Road, the Rebel Yell went up and down the ranks. Across the field, Union 2nd Lieutenant Frank E. Moran of the 73rd New York Infantry, known as the 2nd Fire Zouaves, observed the Mississippians. He recalled that they “came swarming up from the woods, yelling like demons.”

Thanks to the Smithsonian.com we can hear the old Rebel Yell. The Smithsonian last October posted some rare audio and video footage of Union and Confederate veterans. Among the footage was an exclusive clip from the 1930s where Confederate veterans step up to the mic and let out their version of the fearsome rallying cry.

You can watch the video on the Smithsonian site or on YouTube.