They Fought Like Demons: Women Soldiers in the Civil War is a book that document over 250 documented cases of women taking up arms in the civil war.
Popular notions of women during the Civil War center on self-sacrificing nurses, romantic spies, or brave ladies maintaining their home front in the absence of their men. This conventional picture of gender roles does not tell the entire story, however. Men were not the only ones to march off to war. Women bore arms and charged into battle, too. Women lived in germ-ridden camps, languished in appalling prisons, and died miserably, but honorably, for their country and their cause just as men did.
More on the book over at brainpickings.org