Mary Ann Mann Cornelius was an American writer and social reformer. She was a temperance campaigner and the president of the Woman's Christian Temperance Union (W.C.T.U.) of Arkansas. She spent several years in Tacoma, Washington, where she founded a free reading room and circulating library for the youth. Cornelius was the director of the humane society in both Tacoma and Topeka, Kansas. She wrote several novels and supernatural stories, including Little Wolf, Uncle Nathan's Farm, The White Flame, and Why? or A Kansas Girl's Query. She backed women's suffrage. Despite being semi-invalid for many years, she was active in Christian and philanthropic causes. Cornelius' earliest public efforts were to support her husband's work as a pastor. Many desperate women in the church confided in her about their problems with drinking husbands and sons, and Cornelius became involved in the temperance movement, joining the W.C.T.U. In 1885, she was chosen president of the state's W.C.T.U. She organized the first petition drive to close saloons in Little Rock, Arkansas, under the three-mile ordinance. The canvass was acrimonious, with threats to kill Cornelius if she continued to work.