Helmuth Schmidt (born July 4, 1876 in Rostock, Prussia - April 23, 1918 in Detroit, Michigan, United States), also known as the The American Bluebeard, was a German-born American bigamist, murderer and suspected serial killer.
Soon following his arrest in connection with the murder of maid Augusta Steinbach, Schmidt committed suicide in his jail cell.
After searching through his properties, he was connected to the murders of three more women, with additional located jewelry and watches indicating possible other victims in New York and Missouri.