I feel pretty secure with the "skebaugh" = usquebaugh reference, since Mr. Moomaw was a member, and later president, of the Virginia Folklore Society, and knew his song origins perhaps best of any scholar-singer in the region at the time, apart from Arthur Kyle Davis.

However, that's not to say various other refrain words may not have been contemporary with, or previous to, "Skebaugh."

I'd say it's like many another song: the disyllable attracted several different words that fit the rhythm, and the song framework almost certainly goes back earlier than any of them.

Moreover, drinking songs heard on top of a bottle or two tend to come through fuzzy at best. So there's every reason to believe that from Year One on, some who sang the refrain didn't know what the word was, and sang it any old how.

Lighter, that's an interesting guess about "Mademoiselle" -- it does indeed sound something like a major-key version of "When Johnny Comes Marching Home."

"Skebaugh" has an ABC as follows. You'll see it's not exactly "Mademoiselle," though it has points of resemblance.

Hope the notes arrive approximately on top of the syllables they represent.

What a great song this is. I've sung it periodically ever since '55, and its brawny fun never fails.

Bob

SKEBAUGH

.G   C    C    C    C      D   E E E
In eighteen hundred and fifty-one
.G    C          E   .G
Skebaugh, says I,
.G   C    C      C    C      D    E E E
In eighteen hundred and fifty-one,
.G    C          E   .G
Skebaugh, says I,
G    G      G       G G      E      F   F F
In eighteen hundred and fifty-one
D       E       E      E   C   D    D D
We licked the Yankees at Bull Run,
E       F       G       F      E       D   
And we'll   all   drink   stone blind,
C . B       C       D E    D    C
Johnny come fill up the bowl.