In 1918, the German engineer Arthur Scherbius filed a patent application for a rotor ciphering machine. In 1923, the Enigma A was offered to commercially interested costumers at a trade fair in Bern. After Scherbius died in an accident in 1929, his company was bought by Heimsoeth & Rinke in 1934. Thousands of Enigma machines were used by the German Wehrmacht.

After 1938, the Swiss Armed forces bought a number of 265 Enigma machines, which were of the commercially available „Enigma K“ type.

By the end of the war, a total of around 40,000 cipher machines had been manufactured in various factories; after the end of the war, the company ceased operations.

• Heimsoeth & Rinke on Wikipedia