Westfalia is the designation of various specially converted Volkswagen camper vans. It is named for Westfalia-Werke, the contractor that built the vans, which is headquartered in the town of Rheda-Wiedenbrück located in the Westphalia region of Germany.
Westfalia-Werke also converted non-VW vans, and made trailers and other products, but they were best known for their Volkswagen camper conversions. Westfalia began converting Volkswagen buses in 1951. Their famous "pop-top" package was added later, and became very popular on the second-generation VW Bus from 1968-1979, its successor the Vanagon, and then the T4 EuroVan, which was discontinued in 2003. This design also inspired many imitators, with dozens of other companies worldwide offering poptop van conversions. Therefore, not all pop-top Volkswagens are Westfalia conversions (although in the U.S., the Westfalia conversion was by far the most common). Conversely, not all Volkswagen Westfalia conversions had poptops or cooking facilities. Volkswagen offered a "Weekender" package in the 1970s with a Westfalia interior but no poptop. Later, some Vanagon conversions were offered with a pop-top and interior table, but lacked cooking facilities and instead included a luggable 12-volt refrigerator.
In 1999, DaimlerChrysler purchased a 49% stake in Westfalia-Werke's van conversion division, and in 2001 absorbed the remaining 51%. Of course, since DaimlerChrysler is a Volkswagen competitor, this spelled the end of the Volkswagen-Westfalia partnership. While Volkswagen still offers pop-top camper conversions in Europe, they now do the conversion themselves. Meanwhile, Westfalia now makes high-roof (rather than pop-top) factory camper conversions for Mercedes vans (distributed in the U.S. by Airstream and badged as Dodge Sprinters). They also provide automotive accessories to BMW, including trailer hitches.