The Black Legion was an organization that splintered from the Ku Klux Klan and operated in the United States in the 1930s. The organization was founded by William Shepard in east central Ohio. The group's total membership, estimated between 20,000 and 30,000, was centered in Detroit, Michigan, though the Legion was also highly active in Ohio and one of its self-described leaders, Virgil "Bert" Effinger, lived and worked in Lima, Ohio.
The Associated Press described the organization on May 31, 1936, "as a group of loosely federated night-riding bands operating in several States without central discipline or common purpose beyond the enforcement by lash and pistol of individual leaders' notions of 'Americanism.'" The death of Charles Poole, kidnapped and murdered in southwest Detroit, caused authorities to finally arrest and successfully try and convict a group of twelve men, thereby ending the reign of the Black Legion.
The Black Legion was organized along paramilitary lines and had five brigades, 16 regiments, 64 battalions, and 256 companies. Although its members boasted that there were one million legionnaires in Michigan, it probably had only between 20,000 and 30,000 members in the state in the 1930s, one third of whom lived in Detroit.
The April 1, 1937 episode of True Detective Mysteries, a radio show based on the magazine of the same title, was based directly on the Black Legion and the murder of Poole.