a Confederate guerrilla during the American Civil War
<noun.person>
Bushwhacker \Bush"whack`er\, n. 1. One accustomed to beat about, or travel through, bushes. [U.S.]
They were gallant bushwhackers, and hunters of raccoons by moonlight. --W. Irving.
2. A guerrilla; a marauding assassin; one who pretends to be a peaceful citizen, but secretly harasses a hostile force or its sympathizers. [U.S.] --Farrow.