The Lehr und Wehr Verein ("Educational and Defense Society") was a Chicago-based socialist military organization founded in 1875. The group had been formed to counter the armed private armies of companies in Chicago.
The Lehr und Wehr Verein (LWV) was registered with the Illinois state authorities on April 19, 1875 with about 30 Bohemian and German members. The organization used to train and drill in anticipation of an envisaged confrontation between Capital and Labor.
In 1879 the State Legislature passed an act establishing a state militia and obliging all other militias to obtain a license from the Governor. That December the LWV paraded 40 strong, armed with rifles. They were headed by Herman Presser, a socialist worker armed with a saber. Presser was arrested, as the organization had no license.
Lawyers for the LWV argued that the new law breached the Second Amendment to the United States Constitution. Presser v. Illinois became a test case which proceeded through the criminal courts, to the Illinois Supreme Court, and to the Supreme Court of the United States. In each court Presser conviction was upheld The Lehr und Wehr Verein never again paraded in public.