BMW MT 55
BMW's origins can be traced back to three separate German companies: Rapp Motorenwerke, Bayerische Flugzeugwerke and Automobilwerk Eisenach. The history of the name itself begins with Rapp Motorenwerke, an aircraft engine manufacturer. In April 1917, following the departure of the founder Karl Friedrich Rapp, the company was renamed Bayerische Motoren Werke (BMW). BMW's first product was the BMW IIIa aircraft engine. The IIIa engine was known for good fuel economy and high-altitude performance. The resulting orders for IIIa engines from the German military caused rapid expansion for BMW.
After the end of World War I in 1918, BMW was forced to cease aircraft-engine production by the terms of the Versailles Armistice Treaty. To maintain in business, BMW produced farm equipment, household items and railway brakes. In 1922, former major shareholder Camillo Castiglioni purchased the rights to the name BMW, which led to the company descended from Rapp Motorenwerke being renamed Süddeutsche Bremse AG (known today as Knorr-Bremse). Castiglioni was also an investor in another aircraft company, called "Bayerische Flugzeugwerke", which he renamed BMW. The disused factory of Bayerische Flugzeugwerke was re-opened to produce engines for busses, trucks, farm equipment and pumps, under the brand name BMW. BMW's corporate history considers the founding date of Bayerische Flugzeugwerke (7 March 1916) to be the birth of the company.