Mary Edwards Walker, one of the nation's 1.8 million women veterans, was the only one to earn the Congressional Medal of Honor, for her service during the Civil War. She, along with thousands of other women, were honored in the newly-dedicated Women in Military Service for America Memorial in October 1997.When war broke out, she came to Washington and tried to join the Union Army. Denied a commission as a medical officer, she volunteered anyway, serving as an acting assistant surgeon -- the first female surgeon in the US Army. As an unpaid volunteer, she worked in the US Patent Office Hospital in Washington. Later, she worked as a field surgeon near the Union front lines for almost two years.