In 1873 Heinrich Stoll and Christian Schmidt founded a knitting machine factory in Riedlingen, Germany. After some time the founders each went their own way. Stoll moved his part of the factory to Reutlingen in 1879. Schmidt went to Neckarsulm in 1884 and founded NSU: the Neckarsulmer Strickmaschinefabrik.
So the company started out as a manufacturer of knitting machines in 1873. Then came bicycles, and by 1892, the knitting machines were completely replaced by the bicycl.se Not only complete bikes, but also parts for other companies. At that point the name NSU was created, just taking three letters from the name Neckarsulm.
During the first years of the twentieth century, motorbikes. In 1905, the first cars were build, and some were even used (succesfully) in racing.
In the 1928, the manufacturing of cars was stopped. Fiat acquired the rights to the NSU name from a company which had run into severe financial difficulties.
The FIAT company "NSU Automobil AG" started building NSU cars again in 1957, at the same time the then called NSU Werke AG did the same with the (then) new Prinz. This lead to much confusion, and in 1959, the FIAT cars where marked NSU/FIAT. In 1960 the NSU company was renamed to "NSU Motorenwerke AG".
The Sport Prinz was introduced in 1959, followed by the Prinz 4 in 1961.
In 1964, the first production car using a Wankel rotary engine was introduced after 8 years of development of the engine: the Wankel Spider.
On March 10, 1969, a contract was signed uniting AUTO UNION GmbH and NSU Motor Works AG and establishing a new joint company, AUDI NSU AUTO UNION AG. Auto Union Gmbh was partially owned by the Volkswagen AG.
There had been too many problems with the revolutionary wankel engines for NSU to keep going. The last car produces by NSU was the Ro 80. This model was one of the first luxury cars with a wankel engine; this, and several other items, made the car one of the last 26 contenders in the Car Of The Century Celebration.