In 1969 Volkswagenwerk AG engineered the merger of Auto Union GmbH and the Neckarsulm-based NSU Motorenwerke AG. The new company was known as Audi NSU Auto Union AG and had its registered offices in Neckarsulm.
NSU was founded in 1873 in Riedlingen on the Danube, by two Swabian mechanics, Christian Schmidt and Heinrich Stoll. Seven years later a move to Neckarsulm took place. For its first twenty years, it manufactured knitting machines, but in 1886 the company, whose original name was Neckarsulmer Strickmaschinenfabrik (Neckarsulm Knitting Machine Factory), diversified into bicycles. From then on, two-wheeled vehicles were to have a decisive influence on the company's fortunes. Motorcycle production commenced at NSU in 1901, and five years later the first motor car was built. Motor car production was abandoned, however, in 1929, to allow the company to concentrate on building two-wheelers. It was almost thirty years later, in 1958, before car production recommenced in Neckarsulm. On March 10, 1969, Auto Union GmbH of Ingolstadt merged with NSU Motorenwerke AG of Neckarsulm. The new company bearing the name Audi NSU Auto Union AG, with its head offices in Neckarsulm, was established retrospectively as of January 1, 1969.
The last NSU left the production line in March 1977, and from then on the company manufactured Audi cars exclusively. Streamlining the company's rather cumbersome name of Audi NSU Auto Union AG was discussed, and with the objective of giving the company and its products the same name, Audi NSU Auto Union AG was renamed AUDI AG in 1985. At the same time the registered offices were transferred from Neckarsulm to Ingolstadt.