As a member of the Museum of the Confederacy, I receive their email newsletters on a regular basis. In one of the latest ones, there was some news about fellow SCV member, and President/CEO of the MOC, Waite Rawls, III's work regarding the Museum of the Confederacy's efforts in preserving the sound which sent chills up the spine of many a Union soldier. Regarding the origin of the Rebel Yell, my guess is that it likely originated spontaneously during the heat of a charge, very possibly from the **ancestral spirit of some Scots-Irish plowboy with blood, fear, and anger in his eyes. Part one below:
And now, fellow SCV member and historical artist, Henry Kidd explains further in Part two . . .
As a kid, my friends and I had our own version (not quite as bone-chilling) of the Rebel Yell which we shouted as we explored the woods, streams, and fields where our ancestors had spilled their blood defending their homes. You might also be interested in my previous post on this subject.
**Update: After reading the MOC's quarterly magazine piece (Winter 2010) about this, I discovered they too considered the Scots-Irish connection to the Rebel Yell:
"Some believe it descends from a Scottish war cry said to have been used by the legendary forces of Robert Bruce and William Wallace and brought to America with the tide of Scots-Irish immigrants."