ERMA Werke (Erfurter Maschinenfabrik, often simply written as Erma) was a German small arms manufacturer that operated from 1924 to 1997. The company traced its history back to a state-owned arms factory in Erfurt, which was closed after Germany's defeat in World War I. The factory's director, Berthold Geipel, along with many of the engineers that worked there, set up Erma in 1924.
During the inter-war period, Erma produced a number of military and sporting guns that achieved commercial success in Germany and abroad. When World War II broke out, Erma became one of the largest suppliers of small arms for the German war effort; it notably produced millions of MP40 submachine guns.
The original Erma factory at Erfurt was captured by the Soviets in 1945; its staff fled west and set up a new factory in Dachau in 1951. Erma briefly attempted to tap into the post-war military market with a series of new designs, but failed to get any adopted and turned their attention for the remainder of their existence towards sporting guns and target pistols. In 1997, the company officially declared bankruptcy and was bought out; the Erma name continues to exist as a brand name only.