The Black Legion was a secret vigilante terrorist group and a white supremacist organization in the Midwestern United States that splintered from the Ku Klux Klan and operated during the Great Depression of the 1930s. The white paramilitary group was founded in the 1920s by William Shepard in east central Ohio in the Appalachian region, as a security force known as the Black Guard in order to protect Ku Klux Klan officers. The Legion became active in chapters throughout Ohio. One of its self-described leaders, Virgil "Bert" Effinger, lived and worked in Lima, Ohio.
In 1931 a chapter was formed in Highland Park, Michigan, expanding to an estimated total membership in the state estimated between 20,000 and 30,000 by the mid-1930s during the Great Depression. Its members were generally native-born Protestant men, many who had migrated from the South. One third of the members lived in Detroit, which had also been a strong center of KKK activity in the 1920s. In May 1936 Charles A. Poole, a Works Progress Administration organizer, was kidnapped from home by a gang of the Black Legion and murdered in southwest Detroit. Authorities arrested and prosecuted a gang of twelve men affiliated with the Legion. Dayton Dean pleaded guilty and testified against numerous other members; ten others were convicted of the murder. Dean and the others were all sentenced to life in prison. One man was acquitted.
At the time of Poole's murder, the Associated Press described the organization 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'."