Mildred Fish was born in Milwaukee, Wisconsin, in 1902. In 1926, she married German lawyer Arvid Harnack. They returned to his native Germany in 1930, where she worked as an editor and writer and he as a member of the German government. They were leaders of the resistance group "Red Orchestra." After their arrests by the Gestapo in 1942, she was sentenced to a six-year prison term, and he was executed. Adolf Hitler personally ordered her case reopened, and she was beheaded on February 16, 1943. Mildred Fish Harnack was the only native-born American known to have been executed by the Gestapo.
Mildred Fish Harnack Day - Enacted April 10, 1986, from the 1985 Laws of Wisconsin, Act 232. - is celebrated in Wisconsin on September 10.