Some time ago I made a search in the Internet about women that disguise themselves as men in some time in History and serve in the army...
There was many "Oscars"... only with different names they were "Mark" "James" "Tom" or "John" but all strong courageous women that make a stand in their time!
One in particular catch my admiration her name was Mary Read or Mark Read as many know her, she was like "our" Oscar raise to be a boy, not by her Father but by her mother that lost a baby boy months before Mary was born, so her mother disguise her as her dead son to receive a heritage from the boy grandmother!
Well Mary grown up as a boy, and went to war were served for 4 years as a cavalry and foot soldier, wend she fall in love with a colleague and confess to him her gender... they married after the war, was end Mary had her calm life as a woman, but her husband died and she was forced to go to the army again, but didn't stay there for long joining a ship as a helper.
Soon after her ship was captured by pirates, and them her pirate life begun wend she joined Calico Jack crew...
Well here, it is a link with her biography if you want to learn more:
http://en.wikipedia.org/wiki/Mary_Read
I'm trying to develop a "graphic novel" project with her story but is just a small idea!