Martha Elizabeth Beall Jennings Mitchell was born in Pine Bluff, Arkansas on September 2, 1918. She grew up the only child of cotton broker George V. Beall and drama teacher Arie Beall (née Ferguson). Living in a rural area, Mitchell's friends lived far away, and she recalled in a "Saturday Evening Post" interview that she mostly grew up playing with the children of her "mammy," or African-American domestic worker, who lived with the family on the farm. As a little girl, she liked to sing, particularly as a member of her church choir. Her mother hoped she would become an opera singer. As a child, she studied singing around the country and, at Northwestern, she studied piano.