[5] Under Hahn's leadership, Volkswagen of America began a national advertising campaign to attract more attention to its quirky Beetle sedan and Microbus wagon.

As the Beetle served a market segment that American car builders did not cover, Volkswagen enjoyed exceptional sales in the U.S. in the 1960s and early 1970s.

[5] Hahn became a beloved figure in the United States before his return to Germany in 1965, having been affectionately nicknamed "Mr. Volkswagen" by VW enthusiasts.

[4] In 1973, Hahn left VW and returned to Hannover, Germany, to lead the German tire company Continental AG.

[5] Under his leadership, Volkswagen entered a cooperation agreement with the Spanish car brand SEAT in 1982, bought a majority interest in 1986, and by 1990 owned the entire company.

"[9] Hahn fired Volkswagen of America president James McLernon, a former Chevrolet engineer who had been tapped by VW to get the Westmoreland plant up and running.

Hahn brought in new management and kept the Westmoreland factory open to produce the second-generation Golf as a hedge against currency fluctuation between the German mark (DM) and the U.S. dollar, but inefficient production and soft sales in North America caused VW to close the plant in 1988.

[5] Hahn could not keep manufacturing and development costs under control in the early 1990s,[7] and he was replaced as Volkswagen CEO by Ferdinand Piëch in 1993.