Theophilus Riesinger (February 27, 1868 - November 9, 1941) was a Roman Catholic priest who was born in Germany and later resided in Marathon, Wisconsin, in the United States.
He was ordained on May 29, 1899 and later was an exorcist. In 1928, he traveled to a convent in Earling, Iowa where he performed the Roman Catholic rite of exorcism on a forty-year-old woman. After twenty-three days of exorcism Father Theophilus was fatigued. Two days before Christmas 1928, the demons were driven out and the woman cried, “My Jesus mercy. Praised be Jesus Christ.”
The incident was written up by Rev. Carl Vogl in German and translated into English by Rev. Celestine Kapsner which he published in the United States as Begone Satan! in 1935. It became a well known case and brought the reality of exorcism to the masses for the first time. Father Riesinger himself wrote about the case in a 1934 book called The Earling Possession Case: An Exposition of the Exorcism of "Mary", a Demoniac.