Mary Elizabeth Clarke was a United States Army officer who was the department head of the Women's Army Corps. She became major general in the United States Army and was the first woman to obtain this rank. She served in the United States Army for thirty six years, the longest ever served for a woman in the United States Army. In 1978 Norwich University awarded her an honorary doctorate in military science. She retired in 1981 and was on the Women in the Services Defense Advisory Committee.

The Women's Army Corps (WAC) was the women's branch of the United States Army. It was created as an auxiliary unit, the Women's Army Auxiliary Corps (WAAC) on 15 May 1942, and converted to an active duty status in the Army of the United States as the WAC on 1 July 1943. Its first director was Colonel Oveta Culp Hobby. The WAC was disbanded in 20 October 1978, and all units were integrated with male units.