Margareta Elisabeth Roos (1696-1772) was a Swedish-Estonian woman and a crossdresser who served as a soldier in the Swedish army under Charles XII of Sweden during the Great Northern War. Some sources wrongly name her as Anna Stina Roos.
She enlisted in the army in 1713, some sources say because she was in love with an officer. She served as a soldier in the battle fields until the end of the war, for eight years, until 1721, during which time she was noted for great courage and promoted to the rank of non-commissioned officer. She is reported to have been a part of the regiment of General Düker. Apparently, she was never discovered. She is said to have ben so "masculine" in her ways regarding alcohol usage and foul language that no-one suspected her of being a woman, and she was also a tall as a man.
After the war, she worked as head butler at the household of a countess, guessed by some sources to be Hedvig Vilhelmina Oxenstierna, Countess Dücker by marriage, for three years. During an illness, however, a maid discovered her to be a woman and told the countess. The countess agreed to keep quiet, but arranged a marriage for her with an officer of Scottish origin, John Gustave Irving, himself a veteran of the war. This was said to have happened in 1724. They lived together for twenty years, and after his death in 1744, she moved to Köping. Her daughter with Irving, Margareta Charlotta, married the vicar of Bro, Nils Larsson Sundell, and Margareta spent much of her old age with her daughter and son-in-law; during her old age, she was said to often give proof of a "male and courageuos mind".
Unlike the stories of Ulrika Eleonora Stålhammar, and Elisa Bernerström, other Swedish wartime crossdressers, the story of Margareta has never been confirmed, and may or may not be true. Her story was told to a priest by her relatives in 1843, seventy-one years after her death.