In 1926, Mitchell made his home with his wife Elizabeth at the Boxwood Farm in Middleburg, Virginia, which remained his primary residence until his death. He died of a variety of ailments, including a bad heart and an extreme case of influenza, in a hospital in New York City on February 19, 1936, at the age of 56, and was buried at Forest Home Cemetery in Milwaukee, Wisconsin. None of Mitchell's children from his first marriage attended the funeral. His widow, Elizabeth, married Thomas Bolling Byrd, the brother of Virginia governor Harry F. Byrd Sr. and explorer Richard E. Byrd.