I want to do something more with my life...maybe I should go to war
Martha Jones wanted to go to war after her husband had been drafted so she changed her appearance to make her look like a man.
When she made it into the war she had started marching towards Antietam. Martha was in constant fear of being discovered, but she knew she would've regretted staying home.
Soon after the battle started Martha ended up being shot in the battle and told the man she had become close with that she was a woman. Martha was one of the many women that fought in the war with the secret identity of a woman.